{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-68170",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-68170",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-08-10T11:59:39.174Z",
    "updatedAt": "2026-08-17T05:00:11.808Z",
    "importedAt": "2026-10-24T01:58:25.636Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "mptcp: fix stale skb->sk reference on subflow close",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix stale skb->sk reference on subflow close\n\nThe backlog list is updated by mptcp_data_ready() under\nmptcp_data_lock(). The cleanup of backlog references to a closing\nsubflow, however, was performed in mptcp_close_ssk(), before\n__mptcp_close_ssk() acquires the ssk lock, and while holding neither\nthe ssk lock nor mptcp_data_lock().\n\nBecause that traversal ran without mptcp_data_lock(), concurrent softirq\nRX processing on another CPU (subflow_data_ready() -> mptcp_data_ready()\n-> __mptcp_add_backlog(), under mptcp_data_lock()) could add a backlog\nentry referencing the ssk while the cleanup loop was in progress. Such\nan entry could be missed by the cleanup, or the concurrent list update\ncould corrupt the traversal, leaving skb->sk pointing at the ssk after\nit is freed.\n\nA later mptcp_backlog_purge() then dereferences the stale pointer,\ntriggering a warning in inet_sock_destruct() (ssk->sk_rmem_alloc != 0)\nfollowed by a use-after-free in mptcp_backlog_purge().\n\nFix this by moving the backlog cleanup into __mptcp_close_ssk(), after\nsubflow->closing is set to 1 and while the ssk lock is still held,\nserialized under mptcp_data_lock(). The cleanup runs only on the push\npath (MPTCP_CF_PUSH), where backlog references accumulate; on other\nteardown paths the caller already handles cleanup.\n\nWith subflow->closing set and mptcp_data_lock() held across the purge,\nany concurrent mptcp_data_ready() either completes its enqueue before\nthe purge runs and is caught, or observes closing=1 and bails out. Once\nmptcp_data_unlock() is reached, no new skb referencing the ssk can be\nenqueued, so the cleanup is exhaustive.\n\nRemove the unprotected traversal from mptcp_close_ssk() entirely.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "ee458a3f314e9c669ddd227bf5ab08354d9e75cc",
              "status": "affected",
              "versionType": "git",
              "lessThan": "625fc6060864889fe3d370cdeffbbab762af3cb4"
            },
            {
              "version": "ee458a3f314e9c669ddd227bf5ab08354d9e75cc",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bd7aae448f6ee9d82599a4474664de1e6e91a535"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.19",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.19"
            },
            {
              "version": "7.1.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "version": "7.2",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}