Vulnerability-Lookup

ubuntu-cve-2026-75900

Vulnerability from osv_ubuntu

Published

2026-08-19 08:17

Modified

2026-09-11 18:23

Summary

Details

An out-of-bounds read vulnerability was found in swtpm's SWTPM_NVRAM_CheckHeader() function. The entry guard checks the buffer length against sizeof(bh), where bh is a pointer, instead of sizeof(*bh), the actual struct size. This allows an undersized buffer to pass validation, causing a 2-byte heap overread on 64-bit systems (6 bytes on 32-bit) when accessing the totlen field. This may cause daemon termination on some platforms and leaks heap data to the log.

Severity

6.1 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-75900	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-75900	REPORT
	https://github.com/stefanberger/swtpm/pull/1155	REPORT
	https://access.redhat.com/security/cve/CVE-2026-75900	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "swtpm",
            "binary_version": "0.6.3-0ubuntu3.3"
          },
          {
            "binary_name": "swtpm-tools",
            "binary_version": "0.6.3-0ubuntu3.3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "swtpm",
        "purl": "pkg:deb/ubuntu/swtpm@0.6.3-0ubuntu3.3?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.6.1-0ubuntu1",
        "0.6.1-0ubuntu2",
        "0.6.1-0ubuntu3",
        "0.6.1-0ubuntu4",
        "0.6.1-0ubuntu5",
        "0.6.3-0ubuntu1",
        "0.6.3-0ubuntu2",
        "0.6.3-0ubuntu3",
        "0.6.3-0ubuntu3.1",
        "0.6.3-0ubuntu3.2",
        "0.6.3-0ubuntu3.3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "swtpm",
            "binary_version": "0.7.3-0ubuntu5.24.04.1"
          },
          {
            "binary_name": "swtpm-tools",
            "binary_version": "0.7.3-0ubuntu5.24.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "swtpm",
        "purl": "pkg:deb/ubuntu/swtpm@0.7.3-0ubuntu5.24.04.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.7.3-0ubuntu2",
        "0.7.3-0ubuntu3",
        "0.7.3-0ubuntu5",
        "0.7.3-0ubuntu5.24.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "swtpm",
            "binary_version": "0.10.1+ds-1ubuntu3"
          },
          {
            "binary_name": "swtpm-libs",
            "binary_version": "0.10.1+ds-1ubuntu3"
          },
          {
            "binary_name": "swtpm-tools",
            "binary_version": "0.10.1+ds-1ubuntu3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "swtpm",
        "purl": "pkg:deb/ubuntu/swtpm@0.10.1+ds-1ubuntu3?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.7.3-0ubuntu8",
        "0.7.3-0ubuntu9",
        "0.10.1+ds-1ubuntu2",
        "0.10.1+ds-1ubuntu3"
      ]
    }
  ],
  "aliases": [],
  "details": "An out-of-bounds read vulnerability was found in swtpm\u0027s SWTPM_NVRAM_CheckHeader() function. The entry guard checks the buffer length against sizeof(bh), where bh is a pointer, instead of sizeof(*bh), the actual struct size. This allows an undersized buffer to pass validation, causing a 2-byte heap overread on 64-bit systems (6 bytes on 32-bit) when accessing the totlen field. This may cause daemon termination on some platforms and leaks heap data to the log.",
  "id": "UBUNTU-CVE-2026-75900",
  "modified": "2026-09-11T18:23:04Z",
  "published": "2026-08-19T08:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-75900"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-75900"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/stefanberger/swtpm/pull/1155"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-75900"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-75900"
  ]
}

CVE-2026-75900 (GCVE-0-2026-75900)

Vulnerability from cvelistv5 – Published: 2026-08-19 07:44 – Updated: 2026-08-21 19:22

Title

Swtpm: swtpm: out-of-bounds read in swtpm_nvram_checkheader due to sizeof(pointer) vs sizeof(struct) mismatch

Summary

Severity

6.1 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-21 19:22 UTC

CWE

CWE-125 - Out-of-bounds Read

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-75900	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2517910	issue-trackingx_refsource_REDHAT

Impacted products

3 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-19 07:30

Credits

Red Hat would like to thank Suraj Theekshana (株式会社CyberCrew) for reporting this issue.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-75900",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-21T19:22:31.516001Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-21T19:22:41.001Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "swtpm",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
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          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected",
          "packageName": "virt:rhel/swtpm",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "swtpm",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Red Hat would like to thank Suraj Theekshana (\u682a\u5f0f\u4f1a\u793eCyberCrew) for reporting this issue."
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      ],
      "datePublic": "2026-08-19T07:30:46.262Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "An out-of-bounds read vulnerability was found in swtpm\u0027s SWTPM_NVRAM_CheckHeader() function. The entry guard checks the buffer length against sizeof(bh), where bh is a pointer, instead of sizeof(*bh), the actual struct size. This allows an undersized buffer to pass validation, causing a 2-byte heap overread on 64-bit systems (6 bytes on 32-bit) when accessing the totlen field. This may cause daemon termination on some platforms and leaks heap data to the log."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
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            "version": "3.1"
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              "description": "Out-of-bounds Read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
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      "providerMetadata": {
        "dateUpdated": "2026-08-19T09:53:29.480Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
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      "references": [
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          "tags": [
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            "x_refsource_REDHAT"
          ],
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        },
        {
          "name": "RHBZ#2517910",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517910"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-08-14T00:00:00.000Z",
          "value": "Reported to Red Hat."
        },
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          "lang": "en",
          "time": "2026-08-19T07:30:46.262Z",
          "value": "Made public."
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      ],
      "title": "Swtpm: swtpm: out-of-bounds read in swtpm_nvram_checkheader due to sizeof(pointer) vs sizeof(struct) mismatch",
      "workarounds": [
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          "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.\nFixed version: 0.10.2"
        }
      ],
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      "x_redhatCweChain": "CWE-125: Out-of-bounds Read"
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    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-75900",
    "datePublished": "2026-08-19T07:44:35.968Z",
    "dateReserved": "2026-08-18T14:30:48.257Z",
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    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.