{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f2283680a80571ca82d710bc6ecd8f8beac67d63"
            },
            {
              "fixed": "70b4c414889492c522b6e4331562360f49be2361"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "9f297df20d93411c0b4ddad7f88ba04a7cd36e77"
            },
            {
              "fixed": "9a7166f0ef8cbb7bb48dd05e2471d995566003f5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d"
            },
            {
              "fixed": "c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683"
            },
            {
              "fixed": "6aef1765d6807e0f027cd87f6ac973eb0879a46d"
            },
            {
              "fixed": "80824c7e527b70cf9039534e60aff592e8f209d1"
            },
            {
              "fixed": "4cb537ae4f37d7d0f617815ed4bed7173fb50861"
            },
            {
              "fixed": "0e55f63dd08f09651d39e1b709a91705a8a0ddcb"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.15.145"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.1.71"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "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": "6.6.0"
            },
            {
              "fixed": "6.12.80"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.18.21"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "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-2026-31478.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()\n\nAfter this commit (e2b76ab8b5c9 \"ksmbd: add support for read compound\"),\nresponse buffer management was changed to use dynamic iov array.\nIn the new design, smb2_calc_max_out_buf_len() expects the second\nargument (hdr2_len) to be the offset of -\u003eBuffer field in the\nresponse structure, not a hardcoded magic number.\nFix the remaining call sites to use the correct offsetof() value.",
  "id": "CVE-2026-31478",
  "modified": "2026-07-08T05:38:10.637112969Z",
  "published": "2026-04-22T13:54:06.157Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0e55f63dd08f09651d39e1b709a91705a8a0ddcb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4cb537ae4f37d7d0f617815ed4bed7173fb50861"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6aef1765d6807e0f027cd87f6ac973eb0879a46d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/70b4c414889492c522b6e4331562360f49be2361"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/80824c7e527b70cf9039534e60aff592e8f209d1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9a7166f0ef8cbb7bb48dd05e2471d995566003f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31478.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31478"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()"
}