Vulnerability-Lookup

rlsa-2026:61247

Vulnerability from osv_rocky

Published

2026-08-31 12:05

Modified

2026-09-02 12:12

Summary

Moderate: libxml2 security update

Details

The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fix(es):

libxml2: mingw-libxml2: libxml2: Denial of Service via crafted XML input due to use-after-free (CVE-2026-6653)
libxml2: libxml2: Arbitrary code execution in xmlcatalog utility via buffer overflow (CVE-2026-11979)

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.

Severity

5.9 (Medium)


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

Credits

Rocky Enterprise Software Foundation

Red Hat

References

URL

Type

	https://errata.rockylinux.org/RLSA-2026:61247	ADVISORY
	https://bugzilla.redhat.com/show_bug.cgi?id=2491354	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2494191	REPORT
	https://access.redhat.com/errata/RHSA-2026:61247	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "libxml2",
        "purl": "pkg:rpm/rocky-linux/libxml2?distro=rocky-linux-9\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "BaseOS"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:2.9.13-14.el9_8.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:61247"
  },
  "details": "The libxml2 library is a development toolbox providing the implementation of various XML standards.\n\nSecurity Fix(es):\n\n* libxml2: mingw-libxml2: libxml2: Denial of Service via crafted XML input due to use-after-free (CVE-2026-6653)\n\n* libxml2: libxml2: Arbitrary code execution in xmlcatalog utility via buffer overflow (CVE-2026-11979)\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.",
  "id": "RLSA-2026:61247",
  "modified": "2026-09-02T12:12:13.180556Z",
  "published": "2026-08-31T12:05:35.058762Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:61247"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2491354"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494191"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:61247"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Moderate: libxml2 security update",
  "upstream": [
    "CVE-2026-11979",
    "CVE-2026-6653"
  ]
}

CVE-2026-11979 (GCVE-0-2026-11979)

Vulnerability from cvelistv5 – Published: 2026-06-29 13:21 – Updated: 2026-06-29 13:59 X_Open Source Disputed

Title

Stack-Based Buffer Overflow in libxml2

Summary

libxml2 is vulnerable to multiple stack-based buffer overflows in the xmlcatalog utility when running in --shell mode. The usershell() function processes user input using fixed-size stack buffers without proper bounds checking. By supplying an overly long input line, an attacker can overflow internal buffers (command, arg, and argv) during input parsing. This results in memory corruption within the stack frame. Successful exploitation may cause a crash or potentially allow arbitrary code execution in the context of the xmlcatalog process. This issue has been fixed in the commit c2e233fc. NOTE: The maintainers of this project did not agree that this issue is a vulnerability and considered it a bug.

Severity

1.8 (Low)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-29 13:59 UTC

CWE

CWE-121 - Stack-based Buffer Overflow

Assigner

CERT-PL ENISA root

References

2 references

URL	Tags
https://cert.pl/en/posts/2026/06/CVE-2026-11979	third-party-advisory
https://gitlab.gnome.org/GNOME/libxml2/-/commit/c…	patch

Impacted products

1 product

Vendor	Product	Version
xmlsoft	libxml2	Affected: 0 , ≤ 2.15.3 (custom)

Credits

Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-11979",
                "options": [
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                "timestamp": "2026-06-29T13:59:12.311421Z",
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          "lang": "en",
          "type": "finder",
          "value": "Micha\u0142 Majchrowicz (AFINE Team)"
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          "lang": "en",
          "type": "finder",
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        }
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          "supportingMedia": [
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        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-253",
          "descriptions": [
            {
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              "value": "CAPEC-253 Remote Code Inclusion"
            }
          ]
        }
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      "metrics": [
        {
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 1.8,
            "baseSeverity": "LOW",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:L/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-121",
              "description": "CWE-121: Stack-based Buffer Overflow",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-29T13:21:42.697Z",
        "orgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
        "shortName": "CERT-PL"
      },
      "references": [
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://cert.pl/en/posts/2026/06/CVE-2026-11979"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://gitlab.gnome.org/GNOME/libxml2/-/commit/c2e233fc1b341685fc99621b2768b503f777a72e"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "tags": [
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      "title": "Stack-Based Buffer Overflow in libxml2",
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    "dateReserved": "2026-06-11T13:20:24.839Z",
    "dateUpdated": "2026-06-29T13:59:18.501Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-6653 (GCVE-0-2026-6653)

Vulnerability from cvelistv5 – Published: 2026-06-22 12:40 – Updated: 2026-06-22 15:51

Title

libxml2: Use after free in xmlParseInternalSubset via improper entity resolution handling

Summary

Use After Free in libxml2's xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity resolution handling.

Severity

7 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-22 15:51 UTC

CWE

CWE-416 - Use after free
CWE-611 - Improper Restriction of XML External Entity Processing

Assigner

canonical mitre root

References

2 references

URL	Tags
https://bugs.launchpad.net/ubuntu/+source/libxml2…	issue-tracking
https://gitlab.gnome.org/GNOME/libxml2/-/work_ite…	issue-tracking

Impacted products

1 product

Vendor	Product	Version
GNOME	libxml2	Affected: 2.9.11 , < 2.11.0 (semver)

Credits

Geoffrey Humphreys

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-6653",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-22T15:51:00.508541Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-22T15:51:11.554Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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        {
          "defaultStatus": "unaffected",
          "packageName": "libxml2",
          "product": "libxml2",
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          "vendor": "GNOME",
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              "status": "affected",
              "version": "2.9.11",
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            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Geoffrey Humphreys"
        }
      ],
      "descriptions": [
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          "lang": "en",
          "value": "Use After Free in libxml2\u0027s xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity resolution handling."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-242",
          "descriptions": [
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              "value": "CAPEC-242 Code Injection"
            }
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      "metrics": [
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "HIGH",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
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            "baseSeverity": "HIGH",
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            "subIntegrityImpact": "NONE",
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            "valueDensity": "NOT_DEFINED",
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              "value": "GENERAL"
            }
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      "problemTypes": [
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      "providerMetadata": {
        "dateUpdated": "2026-06-22T12:40:31.424Z",
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          "url": "https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2141260"
        },
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          "tags": [
            "issue-tracking"
          ],
          "url": "https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1058"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to libxml2 version 2.11.0 or later"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "libxml2: Use after free in xmlParseInternalSubset via improper entity resolution handling"
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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

rlsa-2026:61247

Vulnerability from osv_rocky

CVE-2026-11979 (GCVE-0-2026-11979)

CVE-2026-6653 (GCVE-0-2026-6653)

Tags

Sightings

Nomenclature