{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "b24df3e30cbf48255db866720fb71f14bf9d2f39"
            },
            {
              "fixed": "72eaef1f37a3b6bec11c342736834dc3707be3e4"
            },
            {
              "fixed": "491e33144dee872cffda207f6fcb09260728f803"
            },
            {
              "fixed": "8749946579708ea0d339034bb7f423a67dbe89cf"
            },
            {
              "fixed": "96c436e4b010711452b2872558938f4ef276492a"
            },
            {
              "fixed": "858d5ac22cb889266993e7670f9f0c4f4aeedd78"
            },
            {
              "fixed": "05762c5bc1cfdcac36747994fde2c04387a457f1"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.19.0"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.54"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98171.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs\n\nFix several related bounds checking and pointer lifecycle issues in\nreceive_encrypted_standard()'s handling of compound encrypted frames:\n\n- Clear next_buffer after assigning it to server-\u003ebigbuf. A stale\n  next_buffer pointer can lead to a use-after-free on subsequent\n  error paths.\n- Update pdu_length to the decrypted plaintext size (buf_size). Using\n  the pre-decryption length allows NextCommand to point into stale\n  ciphertext residue.\n- Reject next_cmd values smaller than MID_HEADER_SIZE(server).\n- Fix an integer overflow in the upper bound check by verifying\n  pdu_length - next_cmd \u003c MID_HEADER_SIZE(server), ensuring the\n  trailing slice is large enough for a header.",
  "id": "CVE-2026-98171",
  "modified": "2026-10-08T02:30:58.784893807Z",
  "published": "2026-10-06T08:44:15.927Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/05762c5bc1cfdcac36747994fde2c04387a457f1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/491e33144dee872cffda207f6fcb09260728f803"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/72eaef1f37a3b6bec11c342736834dc3707be3e4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/858d5ac22cb889266993e7670f9f0c4f4aeedd78"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8749946579708ea0d339034bb7f423a67dbe89cf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/96c436e4b010711452b2872558938f4ef276492a"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98171.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98171"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "smb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs"
}