FKIE_CVE-2026-68137

Vulnerability from fkie_nvd - Published: 2026-08-10 13:19 - Updated: 2026-08-19 17:20
Severity
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/x25: fix use-after-free in x25_kill_by_neigh() x25_kill_by_neigh() walks the global X.25 socket list looking for sockets attached to a terminating neighbour. x25_list_lock protects list membership while the lookup is in progress, but it does not pin a socket's lifetime after the lock is dropped. The function currently drops x25_list_lock before calling lock_sock(s). A concurrent close can run x25_release(), remove the same socket from x25_list, and drop the last socket reference in that window. The neighbour teardown path can then lock or inspect a freed struct sock/struct x25_sock. Take sock_hold(s) while x25_list_lock still proves that the list entry is live, then drop the temporary reference after the socket has been locked, rechecked, and released. Recheck x25_sk(s)->neighbour after lock_sock(), because another path may have disconnected the socket before this path acquired the socket lock. Restart the list walk after each disconnect because the list lock was dropped and the previous iterator state may no longer be valid. A QEMU/KASAN run against origin/master reproduced a slab-use-after-free in x25_kill_by_neigh().
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3f4fe26c20c30bd5a2e2583e80685def0b27858c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5499e0602d2faafd42c580d25f615903c3fbe11b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5e8a754ac2009a88a7b99ab61eab6296eed360f3
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/610678d4be94b619c751572e8a58de705592cd07
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9aabda553184346f74810e2ee1d96920b4612e3f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c98a454d1a9e1bd09d5fd55a7aa589b199340b88
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/db6b04f6d65549bb1c7bc8e64a92e7b7d03be676
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ec6d91a1bf2ebd767d3d43f6d249ee0ed3f4558a
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/x25/af_x25.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "db6b04f6d65549bb1c7bc8e64a92e7b7d03be676",
              "status": "affected",
              "version": "5c94b6205e87411dbe9dc1ca088eb36b8837fb47",
              "versionType": "git"
            },
            {
              "lessThan": "5e8a754ac2009a88a7b99ab61eab6296eed360f3",
              "status": "affected",
              "version": "409570a619c1cda2e0fde6018a256b9e3d3ba0ee",
              "versionType": "git"
            },
            {
              "lessThan": "c98a454d1a9e1bd09d5fd55a7aa589b199340b88",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "lessThan": "3f4fe26c20c30bd5a2e2583e80685def0b27858c",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "lessThan": "610678d4be94b619c751572e8a58de705592cd07",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "lessThan": "ec6d91a1bf2ebd767d3d43f6d249ee0ed3f4558a",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "lessThan": "9aabda553184346f74810e2ee1d96920b4612e3f",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "lessThan": "5499e0602d2faafd42c580d25f615903c3fbe11b",
              "status": "affected",
              "version": "7781607938c8371d4c2b243527430241c62e39c2",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "dffc859d1d9560da594e4282091781b8d2715f00",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "858642789ada1b48630f322e59416ca9fca3e6b7",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4c240c5a105557e4546d0836e694868f22fd09b0",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9acf05b4e7b55fdb712ef7b331dbce5bcd391d0f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4a279d7ee1c65411b4055ecd428b8aa2b1711c1f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "671529db75e6be777bb1c76aa07c2bdd2992be6d",
              "versionType": "git"
            },
            {
              "lessThan": "5.10.265",
              "status": "affected",
              "version": "5.10.110",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15.216",
              "status": "affected",
              "version": "5.15.33",
              "versionType": "semver"
            },
            {
              "lessThan": "4.10",
              "status": "affected",
              "version": "4.9.311",
              "versionType": "semver"
            },
            {
              "lessThan": "4.15",
              "status": "affected",
              "version": "4.14.276",
              "versionType": "semver"
            },
            {
              "lessThan": "4.20",
              "status": "affected",
              "version": "4.19.238",
              "versionType": "semver"
            },
            {
              "lessThan": "5.5",
              "status": "affected",
              "version": "5.4.189",
              "versionType": "semver"
            },
            {
              "lessThan": "5.17",
              "status": "affected",
              "version": "5.16.19",
              "versionType": "semver"
            },
            {
              "lessThan": "5.18",
              "status": "affected",
              "version": "5.17.2",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/x25/af_x25.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "lessThan": "5.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.265",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.216",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.183",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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\nnet/x25: fix use-after-free in x25_kill_by_neigh()\n\nx25_kill_by_neigh() walks the global X.25 socket list looking for sockets\nattached to a terminating neighbour. x25_list_lock protects list membership\nwhile the lookup is in progress, but it does not pin a socket\u0027s lifetime\nafter the lock is dropped.\n\nThe function currently drops x25_list_lock before calling lock_sock(s). A\nconcurrent close can run x25_release(), remove the same socket from\nx25_list, and drop the last socket reference in that window. The neighbour\nteardown path can then lock or inspect a freed struct sock/struct x25_sock.\n\nTake sock_hold(s) while x25_list_lock still proves that the list entry is\nlive, then drop the temporary reference after the socket has been locked,\nrechecked, and released. Recheck x25_sk(s)-\u003eneighbour after lock_sock(),\nbecause another path may have disconnected the socket before this path\nacquired the socket lock. Restart the list walk after each disconnect\nbecause the list lock was dropped and the previous iterator state may no\nlonger be valid.\n\nA QEMU/KASAN run against origin/master reproduced a slab-use-after-free in\nx25_kill_by_neigh()."
    }
  ],
  "id": "CVE-2026-68137",
  "lastModified": "2026-08-19T17:20:30.880",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-10T13:19:59.253",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3f4fe26c20c30bd5a2e2583e80685def0b27858c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5499e0602d2faafd42c580d25f615903c3fbe11b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5e8a754ac2009a88a7b99ab61eab6296eed360f3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/610678d4be94b619c751572e8a58de705592cd07"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9aabda553184346f74810e2ee1d96920b4612e3f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c98a454d1a9e1bd09d5fd55a7aa589b199340b88"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/db6b04f6d65549bb1c7bc8e64a92e7b7d03be676"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ec6d91a1bf2ebd767d3d43f6d249ee0ed3f4558a"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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.