ksmbd: avoid out of bounds access in decode_preauth_ctxt()

{
  "id": "708262e6a6f6793d2bfc05a2457d66f84f59a015cda603606d0cb77a6b0de0ed",
  "url": "https://osv.dev/vulnerability/CVE-2023-54250",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "ksmbd: avoid out of bounds access in decode_preauth_ctxt()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: ksmbd: avoid out of bounds access in decode_preauth_ctxt() Confirm that the accessed pneg_ctxt->HashAlgorithms address sits within the SMB request boundary; deassemble_neg_contexts() only checks that the eight byte smb2_neg_context header + (client controlled) DataLength are within the packet boundary, which is insufficient. Checking for sizeof(struct smb2_preauth_neg_context) is overkill given that the type currently assumes SMB311_SALT_SIZE bytes of trailing Salt.",
    "evidence": "osv:CVE-2023-54250",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.145",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.25",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.2.12",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2023-54250",
      "aliases": [
        "CVE-2023-54250"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9"
                },
                {
                  "fixed": "39f5b4b313b445c980a2a295bed28228c29228ed"
                },
                {
                  "fixed": "a2f6ded41bec1d3be643c80a5eb97f1680309001"
                },
                {
                  "fixed": "f02edb9debbd36f44efa7567031485892c7df60d"
                },
                {
                  "fixed": "e7067a446264a7514fa1cfaa4052cdb6803bc6a2"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54250.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.15.0"
                },
                {
                  "fixed": "5.15.145"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.25"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.2.12"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54250.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.684262126Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/39f5b4b313b445c980a2a295bed28228c29228ed",
        "https://git.kernel.org/stable/c/a2f6ded41bec1d3be643c80a5eb97f1680309001",
        "https://git.kernel.org/stable/c/e7067a446264a7514fa1cfaa4052cdb6803bc6a2",
        "https://git.kernel.org/stable/c/f02edb9debbd36f44efa7567031485892c7df60d",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54250.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-54250",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54250.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-54250",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 499762,
  "published_at": "2025-12-30T12:15:47.467+00:00"
}