{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2"
            },
            {
              "fixed": "6022da37786701df1fc5dd946a6dcba59d5473b1"
            },
            {
              "fixed": "861f884f5471632c731cbbd612a1c072e391a624"
            },
            {
              "fixed": "588706ebaf8cdb4a4161602949eba365514b1db1"
            },
            {
              "fixed": "a257b41ddfe9e327b26581ad2777f04b23ac73f5"
            },
            {
              "fixed": "08a8f2d13f703924316e9aeac863a88ef50990c7"
            },
            {
              "fixed": "ebe0a55d954fa8da383b6192edb8f763dcb002d5"
            },
            {
              "fixed": "bbd6b2ea966cf57b6ae095cf5a8dbc993cd197a0"
            },
            {
              "fixed": "1cd23ca80784223fa2204e16203f754da4e821f8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.12"
            },
            {
              "fixed": "5.10.261"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.212"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.178"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.145"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.40"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64551.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: validate STALE_COOKIE cause length before reading staleness\n\nWhen an ERROR chunk with a STALE_COOKIE cause is received in the\nCOOKIE_ECHOED state, sctp_sf_do_5_2_6_stale() reads the 4-byte Measure\nof Staleness that follows the cause header:\n\n\terr   = (struct sctp_errhdr *)(chunk-\u003eskb-\u003edata);\n\tstale = ntohl(*(__be32 *)((u8 *)err + sizeof(*err)));\n\nerr is the first cause in the chunk, not the STALE_COOKIE cause that\ncaused the dispatch, and nothing guarantees the staleness field is\npresent. sctp_walk_errors() only requires a cause to be as long as the\n4-byte header, so for a STALE_COOKIE cause of length 4 the read runs\npast the cause, and for a minimal ERROR chunk past skb-\u003etail. The value\nis echoed to the peer in the Cookie Preservative of the reply INIT,\nleaking uninitialized memory.\n\nsctp_sf_cookie_echoed_err() already walks to the STALE_COOKIE cause, so\ncheck its length there and pass it to sctp_sf_do_5_2_6_stale(), which\nreads that cause instead of the first one. A STALE_COOKIE cause too\nshort to hold the staleness field is discarded.\n\nThe read is reachable by any peer that can drive an association into\nCOOKIE_ECHOED, including an unprivileged process using a raw SCTP socket\nin a user and network namespace.",
  "id": "CVE-2026-64551",
  "modified": "2026-07-29T03:30:22.778035771Z",
  "published": "2026-07-27T20:10:40.012Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/08a8f2d13f703924316e9aeac863a88ef50990c7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1cd23ca80784223fa2204e16203f754da4e821f8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/588706ebaf8cdb4a4161602949eba365514b1db1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6022da37786701df1fc5dd946a6dcba59d5473b1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/861f884f5471632c731cbbd612a1c072e391a624"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a257b41ddfe9e327b26581ad2777f04b23ac73f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bbd6b2ea966cf57b6ae095cf5a8dbc993cd197a0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ebe0a55d954fa8da383b6192edb8f763dcb002d5"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64551.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64551"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "sctp: validate STALE_COOKIE cause length before reading staleness"
}