GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-80927 (GCVE-0-2026-80927)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:42 – Updated: 2026-09-11 19:42
VLAI
Title
timekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex()
Summary
In the Linux kernel, the following vulnerability has been resolved: timekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex() If the auxiliary clock is disabled during tk_get_aux_ts64() but is enabled before tks->clock_valid is checked, then uninitialized stackdata will be used in the calculations and indirectly leaked to userspace. The same race window also exists after this change and also for the core timekeeper. But in these cases the only effect would be incorrect adjustments and this is userspace's responsibility to avoid this.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 4eca49d0b621b314ac7c80f363932ec6f6c8abc8 , < fecf1e37775269ad38c172b468ad4ecc3968aa63 (git)
Affected: 4eca49d0b621b314ac7c80f363932ec6f6c8abc8 , < bc59dac50cb45a725f7a50760c7cc72a0964f722 (git)
Affected: 4eca49d0b621b314ac7c80f363932ec6f6c8abc8 , < 4b61084b11bcecce86d03804ff30f8d7b465593c (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.18.50 , ≤ 6.18.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/time/timekeeping.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "fecf1e37775269ad38c172b468ad4ecc3968aa63",
              "status": "affected",
              "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
              "versionType": "git"
            },
            {
              "lessThan": "bc59dac50cb45a725f7a50760c7cc72a0964f722",
              "status": "affected",
              "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
              "versionType": "git"
            },
            {
              "lessThan": "4b61084b11bcecce86d03804ff30f8d7b465593c",
              "status": "affected",
              "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/time/timekeeping.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "lessThan": "6.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntimekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex()\n\nIf the auxiliary clock is disabled during tk_get_aux_ts64() but is enabled\nbefore tks-\u003eclock_valid is checked, then uninitialized stackdata will be\nused in the calculations and indirectly leaked to userspace.\n\nThe same race window also exists after this change and also for the core\ntimekeeper. But in these cases the only effect would be incorrect\nadjustments and this is userspace\u0027s responsibility to avoid this."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-11T19:42:03.257Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/fecf1e37775269ad38c172b468ad4ecc3968aa63"
        },
        {
          "url": "https://git.kernel.org/stable/c/bc59dac50cb45a725f7a50760c7cc72a0964f722"
        },
        {
          "url": "https://git.kernel.org/stable/c/4b61084b11bcecce86d03804ff30f8d7b465593c"
        }
      ],
      "title": "timekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80927",
    "datePublished": "2026-09-11T19:42:03.257Z",
    "dateReserved": "2026-08-26T14:34:25.802Z",
    "dateUpdated": "2026-09-11T19:42:03.257Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-80927",
      "date": "2026-09-17",
      "epss": "0.00166",
      "percentile": "0.06248"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "kernel/time/timekeeping.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "fecf1e37775269ad38c172b468ad4ecc3968aa63",
                    "status": "affected",
                    "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "bc59dac50cb45a725f7a50760c7cc72a0964f722",
                    "status": "affected",
                    "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "4b61084b11bcecce86d03804ff30f8d7b465593c",
                    "status": "affected",
                    "version": "4eca49d0b621b314ac7c80f363932ec6f6c8abc8",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "kernel/time/timekeeping.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.17"
                  },
                  {
                    "lessThan": "6.17",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.50",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.4",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3-rc1",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntimekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex()\n\nIf the auxiliary clock is disabled during tk_get_aux_ts64() but is enabled\nbefore tks-\u003eclock_valid is checked, then uninitialized stackdata will be\nused in the calculations and indirectly leaked to userspace.\n\nThe same race window also exists after this change and also for the core\ntimekeeper. But in these cases the only effect would be incorrect\nadjustments and this is userspace\u0027s responsibility to avoid this."
          }
        ],
        "id": "CVE-2026-80927",
        "lastModified": "2026-09-11T20:18:56.397",
        "metrics": {},
        "published": "2026-09-11T20:18:56.397",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/4b61084b11bcecce86d03804ff30f8d7b465593c"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/bc59dac50cb45a725f7a50760c7cc72a0964f722"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/fecf1e37775269ad38c172b468ad4ecc3968aa63"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-14T13:53:55+00:00",
      "cve": "CVE-2026-80927",
      "id": "CVE-2026-80927",
      "initial_release_date": "2026-09-11T00:00:00+00:00",
      "product_status:known_affected": "90",
      "product_status:known_not_affected": "186",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: timekeeping: Check the return value of tk_get_aux_ts64 in __do_adjtimex()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80927.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "low",
      "current_release_date": "2026-09-15T01:06:20Z",
      "cve": "CVE-2026-80927",
      "id": "CVE-2026-80927",
      "initial_release_date": "2026-09-12T16:37:30Z",
      "product_status:known_not_affected": "353",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-80927",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-80927.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


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.