{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f5a544e3bab78142207e0242d22442db85ba1eff"
            },
            {
              "fixed": "4642ea35c03cf3d3558c009df4757cdb7af3f82d"
            },
            {
              "fixed": "f5300690c23c5ac860499bb37dbc09cf43fd62e6"
            },
            {
              "fixed": "6fafc4c4238e538969f1375f9ecdc6587c53f1cc"
            },
            {
              "fixed": "1d1888b4a7aec518b707f6eca0bf08992c0e8da3"
            },
            {
              "fixed": "a897064a457056acb976e20e3007cdf553de340f"
            },
            {
              "fixed": "e0e5edc81b241c70355217de7e120c97c3429deb"
            },
            {
              "fixed": "9bbb19d21ded7d78645506f20d8c44895e3d0fb9"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.15.0"
            },
            {
              "fixed": "5.15.209"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.131"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.80"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.21"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31476.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: do not expire session on binding failure\n\nWhen a multichannel session binding request fails (e.g. wrong password),\nthe error path unconditionally sets sess-\u003estate = SMB2_SESSION_EXPIRED.\nHowever, during binding, sess points to the target session looked up via\nksmbd_session_lookup_slowpath() -- which belongs to another connection's\nuser. This allows a remote attacker to invalidate any active session by\nsimply sending a binding request with a wrong password (DoS).\n\nFix this by skipping session expiration when the failed request was\na binding attempt, since the session does not belong to the current\nconnection. The reference taken by ksmbd_session_lookup_slowpath() is\nstill correctly released via ksmbd_user_session_put().",
  "id": "CVE-2026-31476",
  "modified": "2026-07-15T01:48:59.966992116Z",
  "published": "2026-04-22T13:54:04.779Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4642ea35c03cf3d3558c009df4757cdb7af3f82d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31476.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31476"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ksmbd: do not expire session on binding failure"
}