Vulnerability-Lookup

RHSA-2026:61625

Vulnerability from csaf_redhat - Published: 2026-08-31 15:54 - Updated: 2026-09-05 09:15

Summary

Red Hat Security Advisory: gzip security update

Severity

Moderate

Notes

Topic: An update for gzip is now available for Red Hat Enterprise Linux 10. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Details: The gzip packages contain the gzip (GNU zip) data compression utility. gzip is used to compress regular files. It replaces them with files containing the .gz extension, while retaining ownership modes, access, and modification times. Security Fix(es): * gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility (CVE-2026-41991) * gzip: gzip: Information disclosure via global buffer overflow in LZH decompression (CVE-2026-41992) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.

CVE-2026-41991

A flaw was found in the `gzexe` utility of GNU `gzip`. When the `mktemp` utility is not available, `gzexe` creates temporary files with predictable names based on the process ID. A local attacker can exploit this by pre-creating a symbolic link to an arbitrary file at the predicted temporary file path. This can lead to a Time-of-Check to Time-of-Use (TOCTOU) condition, allowing the attacker to overwrite arbitrary files on the system.

6.0 (Medium)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:H

CWE-59 - Improper Link Resolution Before File Access ('Link Following')

Affected products

Fixed 13 products

Product	Version	Remediation
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x	—	Vendor Fix fix Workaround
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix Workaround

Threats

Impact Moderate

CVE-2026-41992

A flaw was found in GNU gzip. This global buffer overflow vulnerability in the LZH decompression logic is caused by improper reuse of shared global state between different decompression formats. An attacker can exploit this by providing a specially crafted LZW file followed by a specially crafted LZH file to the `gzip -d` command. This can lead to an out-of-bounds read, potentially resulting in information disclosure.

3.6 (Low)


                        
                          CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L

CWE-125 - Out-of-bounds Read

Affected products

Fixed 13 products

Product	Version	Remediation
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x	—	Vendor Fix fix
Unresolved product id: BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64	—	Vendor Fix fix

Threats

Impact Low

References

16 references

URL	Category
https://access.redhat.com/errata/RHSA-2026:61625	self
https://access.redhat.com/security/updates/classi…	external
https://bugzilla.redhat.com/show_bug.cgi?id=2494158	external
https://security.access.redhat.com/data/csaf/v2/a…	self
https://access.redhat.com/security/cve/CVE-2026-41991	self
https://bugzilla.redhat.com/show_bug.cgi?id=2494158	external
https://www.cve.org/CVERecord?id=CVE-2026-41991	external
https://nvd.nist.gov/vuln/detail/CVE-2026-41991	external
https://cert.pl/en/posts/2026/04/CVE-2026-41991/	external
https://cgit.git.savannah.gnu.org/cgit/gzip.git/c…	external
https://www.gnu.org/software/gzip/	external
https://access.redhat.com/security/cve/CVE-2026-41992	self
https://bugzilla.redhat.com/show_bug.cgi?id=2494159	external
https://www.cve.org/CVERecord?id=CVE-2026-41992	external
https://nvd.nist.gov/vuln/detail/CVE-2026-41992	external
https://cgit.git.savannah.gnu.org/cgit/gzip.git/c…	external

JSON

To clipboard

{
  "document": {
    "aggregate_severity": {
      "namespace": "https://access.redhat.com/security/updates/classification/",
      "text": "Moderate"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Copyright \u00a9 Red Hat, Inc. All rights reserved.",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "summary",
        "text": "An update for gzip is now available for Red Hat Enterprise Linux 10.\n\nRed Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.",
        "title": "Topic"
      },
      {
        "category": "general",
        "text": "The gzip packages contain the gzip (GNU zip) data compression utility. gzip is used to compress regular files. It replaces them with files containing the .gz extension, while retaining ownership modes, access, and modification times.\n\nSecurity Fix(es):\n\n* gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility (CVE-2026-41991)\n\n* gzip: gzip: Information disclosure via global buffer overflow in LZH decompression (CVE-2026-41992)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
        "title": "Details"
      },
      {
        "category": "legal_disclaimer",
        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.",
        "title": "Terms of Use"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://access.redhat.com/security/team/contact/",
      "issuing_authority": "Red Hat Product Security is responsible for vulnerability handling across all Red Hat products and services.",
      "name": "Red Hat Product Security",
      "namespace": "https://www.redhat.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "https://access.redhat.com/errata/RHSA-2026:61625",
        "url": "https://access.redhat.com/errata/RHSA-2026:61625"
      },
      {
        "category": "external",
        "summary": "https://access.redhat.com/security/updates/classification/#moderate",
        "url": "https://access.redhat.com/security/updates/classification/#moderate"
      },
      {
        "category": "external",
        "summary": "2494158",
        "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494158"
      },
      {
        "category": "self",
        "summary": "Canonical URL",
        "url": "https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_61625.json"
      }
    ],
    "title": "Red Hat Security Advisory: gzip security update",
    "tracking": {
      "current_release_date": "2026-09-05T09:15:14+00:00",
      "generator": {
        "date": "2026-09-05T09:15:14+00:00",
        "engine": {
          "name": "Red Hat SDEngine",
          "version": "5.3.16"
        }
      },
      "id": "RHSA-2026:61625",
      "initial_release_date": "2026-08-31T15:54:36+00:00",
      "revision_history": [
        {
          "date": "2026-08-31T15:54:36+00:00",
          "number": "1",
          "summary": "Initial version"
        },
        {
          "date": "2026-08-31T15:54:36+00:00",
          "number": "2",
          "summary": "Last updated version"
        },
        {
          "date": "2026-09-05T09:15:14+00:00",
          "number": "3",
          "summary": "Last generated version"
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_name",
                "name": "Red Hat Enterprise Linux BaseOS (v. 10)",
                "product": {
                  "name": "Red Hat Enterprise Linux BaseOS (v. 10)",
                  "product_id": "BaseOS-10.2.Z",
                  "product_identification_helper": {
                    "cpe": "cpe:/o:redhat:enterprise_linux:10.2"
                  }
                }
              }
            ],
            "category": "product_family",
            "name": "Red Hat Enterprise Linux"
          },
          {
            "branches": [
              {
                "category": "product_version",
                "name": "gzip-0:1.13-4.el10_2.src",
                "product": {
                  "name": "gzip-0:1.13-4.el10_2.src",
                  "product_id": "gzip-0:1.13-4.el10_2.src",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip@1.13-4.el10_2?arch=src"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "src"
          },
          {
            "branches": [
              {
                "category": "product_version",
                "name": "gzip-0:1.13-4.el10_2.aarch64",
                "product": {
                  "name": "gzip-0:1.13-4.el10_2.aarch64",
                  "product_id": "gzip-0:1.13-4.el10_2.aarch64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip@1.13-4.el10_2?arch=aarch64"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debugsource-0:1.13-4.el10_2.aarch64",
                "product": {
                  "name": "gzip-debugsource-0:1.13-4.el10_2.aarch64",
                  "product_id": "gzip-debugsource-0:1.13-4.el10_2.aarch64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debugsource@1.13-4.el10_2?arch=aarch64"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debuginfo-0:1.13-4.el10_2.aarch64",
                "product": {
                  "name": "gzip-debuginfo-0:1.13-4.el10_2.aarch64",
                  "product_id": "gzip-debuginfo-0:1.13-4.el10_2.aarch64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debuginfo@1.13-4.el10_2?arch=aarch64"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "aarch64"
          },
          {
            "branches": [
              {
                "category": "product_version",
                "name": "gzip-0:1.13-4.el10_2.ppc64le",
                "product": {
                  "name": "gzip-0:1.13-4.el10_2.ppc64le",
                  "product_id": "gzip-0:1.13-4.el10_2.ppc64le",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip@1.13-4.el10_2?arch=ppc64le"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debugsource-0:1.13-4.el10_2.ppc64le",
                "product": {
                  "name": "gzip-debugsource-0:1.13-4.el10_2.ppc64le",
                  "product_id": "gzip-debugsource-0:1.13-4.el10_2.ppc64le",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debugsource@1.13-4.el10_2?arch=ppc64le"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
                "product": {
                  "name": "gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
                  "product_id": "gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debuginfo@1.13-4.el10_2?arch=ppc64le"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "ppc64le"
          },
          {
            "branches": [
              {
                "category": "product_version",
                "name": "gzip-0:1.13-4.el10_2.s390x",
                "product": {
                  "name": "gzip-0:1.13-4.el10_2.s390x",
                  "product_id": "gzip-0:1.13-4.el10_2.s390x",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip@1.13-4.el10_2?arch=s390x"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debugsource-0:1.13-4.el10_2.s390x",
                "product": {
                  "name": "gzip-debugsource-0:1.13-4.el10_2.s390x",
                  "product_id": "gzip-debugsource-0:1.13-4.el10_2.s390x",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debugsource@1.13-4.el10_2?arch=s390x"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debuginfo-0:1.13-4.el10_2.s390x",
                "product": {
                  "name": "gzip-debuginfo-0:1.13-4.el10_2.s390x",
                  "product_id": "gzip-debuginfo-0:1.13-4.el10_2.s390x",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debuginfo@1.13-4.el10_2?arch=s390x"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "s390x"
          },
          {
            "branches": [
              {
                "category": "product_version",
                "name": "gzip-0:1.13-4.el10_2.x86_64",
                "product": {
                  "name": "gzip-0:1.13-4.el10_2.x86_64",
                  "product_id": "gzip-0:1.13-4.el10_2.x86_64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip@1.13-4.el10_2?arch=x86_64"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debugsource-0:1.13-4.el10_2.x86_64",
                "product": {
                  "name": "gzip-debugsource-0:1.13-4.el10_2.x86_64",
                  "product_id": "gzip-debugsource-0:1.13-4.el10_2.x86_64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debugsource@1.13-4.el10_2?arch=x86_64"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "gzip-debuginfo-0:1.13-4.el10_2.x86_64",
                "product": {
                  "name": "gzip-debuginfo-0:1.13-4.el10_2.x86_64",
                  "product_id": "gzip-debuginfo-0:1.13-4.el10_2.x86_64",
                  "product_identification_helper": {
                    "purl": "pkg:rpm/redhat/gzip-debuginfo@1.13-4.el10_2?arch=x86_64"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "x86_64"
          }
        ],
        "category": "vendor",
        "name": "Red Hat"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-0:1.13-4.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64"
        },
        "product_reference": "gzip-0:1.13-4.el10_2.aarch64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-0:1.13-4.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le"
        },
        "product_reference": "gzip-0:1.13-4.el10_2.ppc64le",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-0:1.13-4.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x"
        },
        "product_reference": "gzip-0:1.13-4.el10_2.s390x",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-0:1.13-4.el10_2.src as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src"
        },
        "product_reference": "gzip-0:1.13-4.el10_2.src",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-0:1.13-4.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64"
        },
        "product_reference": "gzip-0:1.13-4.el10_2.x86_64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debuginfo-0:1.13-4.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64"
        },
        "product_reference": "gzip-debuginfo-0:1.13-4.el10_2.aarch64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debuginfo-0:1.13-4.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le"
        },
        "product_reference": "gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debuginfo-0:1.13-4.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x"
        },
        "product_reference": "gzip-debuginfo-0:1.13-4.el10_2.s390x",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debuginfo-0:1.13-4.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64"
        },
        "product_reference": "gzip-debuginfo-0:1.13-4.el10_2.x86_64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debugsource-0:1.13-4.el10_2.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64"
        },
        "product_reference": "gzip-debugsource-0:1.13-4.el10_2.aarch64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debugsource-0:1.13-4.el10_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le"
        },
        "product_reference": "gzip-debugsource-0:1.13-4.el10_2.ppc64le",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debugsource-0:1.13-4.el10_2.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x"
        },
        "product_reference": "gzip-debugsource-0:1.13-4.el10_2.s390x",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "gzip-debugsource-0:1.13-4.el10_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 10)",
          "product_id": "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
        },
        "product_reference": "gzip-debugsource-0:1.13-4.el10_2.x86_64",
        "relates_to_product_reference": "BaseOS-10.2.Z"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-41991",
      "cwe": {
        "id": "CWE-59",
        "name": "Improper Link Resolution Before File Access (\u0027Link Following\u0027)"
      },
      "discovery_date": "2026-06-29T12:01:03.862009+00:00",
      "ids": [
        {
          "system_name": "Red Hat Bugzilla ID",
          "text": "2494158"
        }
      ],
      "notes": [
        {
          "category": "description",
          "text": "A flaw was found in the `gzexe` utility of GNU `gzip`. When the `mktemp` utility is not available, `gzexe` creates temporary files with predictable names based on the process ID. A local attacker can exploit this by pre-creating a symbolic link to an arbitrary file at the predicted temporary file path. This can lead to a Time-of-Check to Time-of-Use (TOCTOU) condition, allowing the attacker to overwrite arbitrary files on the system.",
          "title": "Vulnerability description"
        },
        {
          "category": "summary",
          "text": "gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility",
          "title": "Vulnerability summary"
        },
        {
          "category": "other",
          "text": "A flaw was found in the gzexe utility of GNU gzip. When the mktemp utility is not available in the user\u0027s PATH, gzexe creates temporary files with predictable names based on the process ID. A local attacker can exploit this by creating a symbolic link at the predicted temporary file path, leading to a TOCTOU race condition that allows arbitrary file overwrite. On Red Hat Enterprise Linux, mktemp is provided by coreutils which is always installed, making the vulnerable fallback code path effectively unreachable in standard deployments.",
          "title": "Statement"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product\u0027s status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
        "fixed": [
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://access.redhat.com/security/cve/CVE-2026-41991"
        },
        {
          "category": "external",
          "summary": "RHBZ#2494158",
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494158"
        },
        {
          "category": "external",
          "summary": "https://www.cve.org/CVERecord?id=CVE-2026-41991",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-41991"
        },
        {
          "category": "external",
          "summary": "https://nvd.nist.gov/vuln/detail/CVE-2026-41991",
          "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41991"
        },
        {
          "category": "external",
          "summary": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/",
          "url": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/"
        },
        {
          "category": "external",
          "summary": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=4e6f8b24ab823146ab8776f0b7fe486ab34d4269",
          "url": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=4e6f8b24ab823146ab8776f0b7fe486ab34d4269"
        },
        {
          "category": "external",
          "summary": "https://www.gnu.org/software/gzip/",
          "url": "https://www.gnu.org/software/gzip/"
        }
      ],
      "release_date": "2026-06-29T10:15:50.766000+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-08-31T15:54:36+00:00",
          "details": "For details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258",
          "product_ids": [
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
          ],
          "restart_required": {
            "category": "none"
          },
          "url": "https://access.redhat.com/errata/RHSA-2026:61625"
        },
        {
          "category": "workaround",
          "details": "Ensure that the mktemp utility (provided by the coreutils package) is available in PATH when using the gzexe utility. On Red Hat Enterprise Linux, mktemp is installed by default and no additional action is needed.",
          "product_ids": [
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.0,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Moderate"
        }
      ],
      "title": "gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility"
    },
    {
      "cve": "CVE-2026-41992",
      "cwe": {
        "id": "CWE-125",
        "name": "Out-of-bounds Read"
      },
      "discovery_date": "2026-06-29T12:01:09.238155+00:00",
      "ids": [
        {
          "system_name": "Red Hat Bugzilla ID",
          "text": "2494159"
        }
      ],
      "notes": [
        {
          "category": "description",
          "text": "A flaw was found in GNU gzip. This global buffer overflow vulnerability in the LZH decompression logic is caused by improper reuse of shared global state between different decompression formats. An attacker can exploit this by providing a specially crafted LZW file followed by a specially crafted LZH file to the `gzip -d` command. This can lead to an out-of-bounds read, potentially resulting in information disclosure.",
          "title": "Vulnerability description"
        },
        {
          "category": "summary",
          "text": "gzip: gzip: Information disclosure via global buffer overflow in LZH decompression",
          "title": "Vulnerability summary"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product\u0027s status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
        "fixed": [
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
          "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
          "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://access.redhat.com/security/cve/CVE-2026-41992"
        },
        {
          "category": "external",
          "summary": "RHBZ#2494159",
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494159"
        },
        {
          "category": "external",
          "summary": "https://www.cve.org/CVERecord?id=CVE-2026-41992",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-41992"
        },
        {
          "category": "external",
          "summary": "https://nvd.nist.gov/vuln/detail/CVE-2026-41992",
          "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41992"
        },
        {
          "category": "external",
          "summary": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/",
          "url": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/"
        },
        {
          "category": "external",
          "summary": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=63dbf6b3b9e6e781df1a6a64e609b10e23969681",
          "url": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=63dbf6b3b9e6e781df1a6a64e609b10e23969681"
        },
        {
          "category": "external",
          "summary": "https://www.gnu.org/software/gzip/",
          "url": "https://www.gnu.org/software/gzip/"
        }
      ],
      "release_date": "2026-06-29T10:15:57.278000+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-08-31T15:54:36+00:00",
          "details": "For details on how to apply this update, which includes the changes described in this advisory, refer to:\n\nhttps://access.redhat.com/articles/11258",
          "product_ids": [
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
          ],
          "restart_required": {
            "category": "none"
          },
          "url": "https://access.redhat.com/errata/RHSA-2026:61625"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "LOW",
            "baseScore": 3.6,
            "baseSeverity": "LOW",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L",
            "version": "3.1"
          },
          "products": [
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.src",
            "BaseOS-10.2.Z:gzip-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debuginfo-0:1.13-4.el10_2.x86_64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.aarch64",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.ppc64le",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.s390x",
            "BaseOS-10.2.Z:gzip-debugsource-0:1.13-4.el10_2.x86_64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Low"
        }
      ],
      "title": "gzip: gzip: Information disclosure via global buffer overflow in LZH decompression"
    }
  ]
}

CVE-2026-41991 (GCVE-0-2026-41991)

Vulnerability from cvelistv5 – Published: 2026-06-29 10:15 – Updated: 2026-06-29 13:31 X_Open Source

Title

Predictable Temporary File in GNU gzip

Summary

GNU gzip contains a vulnerability in the gzexe utility related to insecure temporary file handling. When the mktemp utility is not available in the user’s PATH, gzexe falls back to constructing a temporary file path based solely on the process ID (PID). This predictable filename is created without exclusive access or existence checks. A local attacker can pre‑create the predicted temporary file path as a symbolic link pointing to an arbitrary file writable by the victim. When gzexe runs, it follows the symlink and overwrites the target file, resulting in a time‑of‑check to time‑of‑use (TOCTOU) condition that allows arbitrary file overwrite. This issue has been fixed in the commit 4e6f8b24ab823146ab8776f0b7fe486ab34d4269

Severity

2 (Low)


                        
                          CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-29 13:31 UTC

CWE

CWE-377 - Insecure Temporary File

Assigner

CERT-PL ENISA root

References

3 references

URL	Tags
https://cert.pl/en/posts/2026/04/CVE-2026-41991/	third-party-advisory
https://www.gnu.org/software/gzip/	product
https://cgit.git.savannah.gnu.org/cgit/gzip.git/c…	patch

Impacted products

1 product

Vendor	Product	Version
GNU	gzip	Affected: 0 , ≤ 1.14 (semver)

Credits

Michał Majchrowicz (AFINE) Marcin Wyczechowski (AFINE)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-41991",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-29T13:31:34.387147Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-29T13:31:46.581Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "gzip",
          "repo": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/",
          "vendor": "GNU",
          "versions": [
            {
              "lessThanOrEqual": "1.14",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Micha\u0142 Majchrowicz (AFINE)"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Marcin Wyczechowski (AFINE)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "GNU gzip contains a vulnerability in the gzexe utility related to insecure temporary file handling. When the mktemp utility is not available in the user\u2019s PATH, gzexe falls back to constructing a temporary file path based solely on the process ID (PID). This predictable filename is created without exclusive access or existence checks.\u003cbr\u003eA local attacker can pre\u2011create the predicted temporary file path as a symbolic link pointing to an arbitrary file writable by the victim. When gzexe runs, it follows the symlink and overwrites the target file, resulting in a time\u2011of\u2011check to time\u2011of\u2011use (TOCTOU) condition that allows arbitrary file overwrite.\u003cbr\u003e\u003cbr\u003e\u003cp\u003eThis issue has been fixed in the commit 4e6f8b24ab823146ab8776f0b7fe486ab34d4269\u003c/p\u003e"
            }
          ],
          "value": "GNU gzip contains a vulnerability in the gzexe utility related to insecure temporary file handling. When the mktemp utility is not available in the user\u2019s PATH, gzexe falls back to constructing a temporary file path based solely on the process ID (PID). This predictable filename is created without exclusive access or existence checks.\nA local attacker can pre\u2011create the predicted temporary file path as a symbolic link pointing to an arbitrary file writable by the victim. When gzexe runs, it follows the symlink and overwrites the target file, resulting in a time\u2011of\u2011check to time\u2011of\u2011use (TOCTOU) condition that allows arbitrary file overwrite.\n\nThis issue has been fixed in the commit 4e6f8b24ab823146ab8776f0b7fe486ab34d4269"
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 2,
            "baseSeverity": "LOW",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-377",
              "description": "CWE-377: Insecure Temporary File",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-29T10:15:50.766Z",
        "orgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
        "shortName": "CERT-PL"
      },
      "references": [
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://www.gnu.org/software/gzip/"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=4e6f8b24ab823146ab8776f0b7fe486ab34d4269"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "tags": [
        "x_open-source"
      ],
      "title": "Predictable Temporary File in GNU gzip",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
    "assignerShortName": "CERT-PL",
    "cveId": "CVE-2026-41991",
    "datePublished": "2026-06-29T10:15:50.766Z",
    "dateReserved": "2026-04-23T08:06:09.511Z",
    "dateUpdated": "2026-06-29T13:31:46.581Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-41992 (GCVE-0-2026-41992)

Vulnerability from cvelistv5 – Published: 2026-06-29 10:15 – Updated: 2026-08-27 11:39 X_Open Source

Title

Global Buffer Overflow in GNU gzip

Summary

GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation. By decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out‑of‑bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer. This issue has been fixed in commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and e7378c2d421be6a286922374425680bbe9ad8b7d.

Severity

6.9 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-29 13:30 UTC

CWE

CWE-126 - Buffer Over-read

Assigner

CERT-PL ENISA root

References

7 references

URL	Tags
https://cert.pl/en/posts/2026/04/CVE-2026-41991/	third-party-advisory
https://www.gnu.org/software/gzip/	product
https://cgit.git.savannah.gnu.org/cgit/gzip.git/c…	patch
https://cgit.git.savannah.gnu.org/cgit/gzip.git/c…	patch
http://www.openwall.com/lists/oss-security/2026/08/23/1
http://www.openwall.com/lists/oss-security/2026/08/25/1
http://www.openwall.com/lists/oss-security/2026/08/27/2

Impacted products

1 product

Vendor	Product	Version
GNU	gzip	Affected: 0 , ≤ 1.14 (custom) cpe:2.3:a:gnu:gzip::::::::

Credits

Michał Majchrowicz (AFINE) Marcin Wyczechowski (AFINE) Elias Hasas (@zer0d4y5)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-41992",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-29T13:30:31.933225Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-29T13:30:43.882Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-08-27T06:04:57.422Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/08/23/1"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/08/25/1"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/08/27/2"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "unlzh.c (LZH decompressor)",
            "unlzw.c (LZW decompressor)",
            "gzip.c (shared global state)"
          ],
          "product": "gzip",
          "repo": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/",
          "vendor": "GNU",
          "versions": [
            {
              "lessThanOrEqual": "1.14",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:gnu:gzip:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "1.14",
                  "versionStartIncluding": "0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ],
          "operator": "OR"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Micha\u0142 Majchrowicz (AFINE)"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Marcin Wyczechowski (AFINE)"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Elias Hasas (@zer0d4y5)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation.\u003cbr\u003eBy decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out\u2011of\u2011bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer.\u003cbr\u003e\u003cbr\u003eThis issue has been fixed in commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and\u003cspan\u003e\u0026nbsp;e7378c2d421be6a286922374425680bbe9ad8b7d.\u003c/span\u003e"
            }
          ],
          "value": "GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation.\nBy decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out\u2011of\u2011bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer.\n\nThis issue has been fixed in commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and\u00a0e7378c2d421be6a286922374425680bbe9ad8b7d."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-540",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-540: Overread Buffers"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-126",
              "description": "CWE-126: Buffer Over-read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-27T11:39:40.630Z",
        "orgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
        "shortName": "CERT-PL"
      },
      "references": [
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://cert.pl/en/posts/2026/04/CVE-2026-41991/"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://www.gnu.org/software/gzip/"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=63dbf6b3b9e6e781df1a6a64e609b10e23969681"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://cgit.git.savannah.gnu.org/cgit/gzip.git/commit/?id=e7378c2d421be6a286922374425680bbe9ad8b7d"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "tags": [
        "x_open-source"
      ],
      "title": "Global Buffer Overflow in GNU gzip",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
    "assignerShortName": "CERT-PL",
    "cveId": "CVE-2026-41992",
    "datePublished": "2026-06-29T10:15:57.278Z",
    "dateReserved": "2026-04-23T08:06:09.511Z",
    "dateUpdated": "2026-08-27T11:39:40.630Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

RHSA-2026:61625

CVE-2026-41991 (GCVE-0-2026-41991)

CVE-2026-41992 (GCVE-0-2026-41992)

Tags

Sightings

Nomenclature