Vulnerability-Lookup

GHSA-WMHQ-5PQ5-8474

Vulnerability from github – Published: 2026-09-11 12:33 – Updated: 2026-09-11 12:33

Details

A symlink-following flaw was found in libvirt's qemuTPMEmulatorPrepareHost() function. The function uses a path-based chown() on the swtpm logfile without checking for symbolic links. A local attacker with access to the swtpm account can replace the logfile with a symlink, causing libvirtd (running as root) to transfer ownership of an arbitrary file to the swtpm user.

Severity

5.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-77159"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T11:16:54Z",
    "severity": "MODERATE"
  },
  "details": "A symlink-following flaw was found in libvirt\u0027s qemuTPMEmulatorPrepareHost() function. The function uses a path-based chown() on the swtpm logfile without checking for symbolic links. A local attacker with access to the swtpm account can replace the logfile with a symlink, causing libvirtd (running as root) to transfer ownership of an arbitrary file to the swtpm user.",
  "id": "GHSA-wmhq-5pq5-8474",
  "modified": "2026-09-11T12:33:25Z",
  "published": "2026-09-11T12:33:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77159"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-77159"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531811"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/libvirt/libvirt/-/work_items/909"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-77159 (GCVE-0-2026-77159)

Vulnerability from cvelistv5 – Published: 2026-09-11 10:32 – Updated: 2026-09-15 15:40

Title

Libvirt: unsafe chown in qemutpmemulatorpreparehost() allows arbitrary file ownership change via symlink

Summary

Severity

5.5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-15 15:39 UTC

CWE

CWE-61 - UNIX Symbolic Link (Symlink) Following

Assigner

redhat CNA under the redhat root

CNA scorecard B 82/100 over 1076 records in the last 180 days details

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-77159	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2531811	issue-trackingx_refsource_REDHAT
https://gitlab.com/libvirt/libvirt/-/work_items/909

Impacted products

5 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
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

2026-09-11 00:00

Credits

Red Hat would like to thank Suraj Theekshana for reporting this issue.

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-77159",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-15T15:39:11.306501Z",
                "version": "2.0.3"
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://gitlab.com/libvirt/libvirt/-/work_items/909"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "libvirt",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "unaffected",
          "packageName": "libvirt",
          "product": "Red Hat Enterprise Linux 6",
          "vendor": "Red Hat"
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          "cpes": [
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          "cpes": [
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        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
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            },
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            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
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        }
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    }
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  "cveMetadata": {
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    "assignerShortName": "redhat",
    "cveId": "CVE-2026-77159",
    "datePublished": "2026-09-11T10:32:29.772Z",
    "dateReserved": "2026-08-20T14:42:32.943Z",
    "dateUpdated": "2026-09-15T15:40:56.022Z",
    "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.

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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.
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