CVE-2026-80778 (GCVE-0-2026-80778)
Vulnerability from cvelistv5
Published
2026-09-04 15:12
Modified
2026-10-19 08:43
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: futex/pi: Reject cross-mm private futex owners A private futex key borrows the waiter's mm without taking an mm_users reference. Nevertheless, attach_to_pi_owner() currently accepts an owner from a different address space and copies the private key into the owner's PI state. When that owner exits, exit_pi_state_list() uses the saved key to find the hash bucket and acquires a reference to the waiter's private hash. If the last user of the waiter's mm exits concurrently, futex_hash_free() frees the hash while the owner still uses its bucket and reference. Prevent this by validating in attach_to_pi_owner() that, for private futexes, the owner mm and waiter mm are the same. Perform the check with the owner's pi_lock held and after validating owner::futex::state to serialize against a concurrent PI-state exit cleanup. [ tglx: Amended comment ]
References
Impacted products
Vendor Product Version
Linux Linux Version: 80367ad01d93ac781b0e1df246edaf006928002f
Version: 80367ad01d93ac781b0e1df246edaf006928002f
Version: 80367ad01d93ac781b0e1df246edaf006928002f
Version: 80367ad01d93ac781b0e1df246edaf006928002f
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/futex/pi.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2b92e5562653b5293529f63b0300837d9dcedbd7",
              "status": "affected",
              "version": "80367ad01d93ac781b0e1df246edaf006928002f",
              "versionType": "git"
            },
            {
              "lessThan": "f7fb3e07752688842cbe0b85cf0d98c2fbf76b68",
              "status": "affected",
              "version": "80367ad01d93ac781b0e1df246edaf006928002f",
              "versionType": "git"
            },
            {
              "lessThan": "43b148d796aa338858792d0167cebdc12b8cb4b9",
              "status": "affected",
              "version": "80367ad01d93ac781b0e1df246edaf006928002f",
              "versionType": "git"
            },
            {
              "lessThan": "59b3732f95dda1fbd2234514d35f4fb6b5bb6d85",
              "status": "affected",
              "version": "80367ad01d93ac781b0e1df246edaf006928002f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/futex/pi.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.47",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.1",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.47",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.11",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.1",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfutex/pi: Reject cross-mm private futex owners\n\nA private futex key borrows the waiter\u0027s mm without taking an mm_users\nreference. Nevertheless, attach_to_pi_owner() currently accepts an owner\nfrom a different address space and copies the private key into the owner\u0027s\nPI state.\n\nWhen that owner exits, exit_pi_state_list() uses the saved key to find the\nhash bucket and acquires a reference to the waiter\u0027s private hash. If the\nlast user of the waiter\u0027s mm exits concurrently, futex_hash_free() frees\nthe hash while the owner still uses its bucket and reference.\n\nPrevent this by validating in attach_to_pi_owner() that, for private\nfutexes, the owner mm and waiter mm are the same. Perform the check with\nthe owner\u0027s pi_lock held and after validating owner::futex::state to\nserialize against a concurrent PI-state exit cleanup.\n\n[ tglx: Amended comment ]"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T08:43:33.681Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2b92e5562653b5293529f63b0300837d9dcedbd7"
        },
        {
          "url": "https://git.kernel.org/stable/c/f7fb3e07752688842cbe0b85cf0d98c2fbf76b68"
        },
        {
          "url": "https://git.kernel.org/stable/c/43b148d796aa338858792d0167cebdc12b8cb4b9"
        },
        {
          "url": "https://git.kernel.org/stable/c/59b3732f95dda1fbd2234514d35f4fb6b5bb6d85"
        }
      ],
      "title": "futex/pi: Reject cross-mm private futex owners",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80778",
    "datePublished": "2026-09-04T15:12:50.117Z",
    "dateReserved": "2026-08-26T14:34:25.792Z",
    "dateUpdated": "2026-10-19T08:43:33.681Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.