{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "83bfbd0bb9025f98fa62b44f93bd67466773d1db"
            },
            {
              "fixed": "5b16a1967a01ad4496a7206a87c3eb16f1df2b05"
            },
            {
              "fixed": "ba22f575de9deeae4ae0859ca4315a7698226237"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89630.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: restore the data_offset bound in is_valid_oplock_break()\n\nCommit 83bfbd0bb902 (\"cifs: Remove the RFC1002 header from smb_hdr\")\nchanged the quantity this bound is measured against.  It used to be\nsrv-\u003etotal_read minus the 4-byte RFC1002 preamble that total_read then\nincluded, so it was the SMB message length.  The same commit stopped\ncounting the preamble, and the mechanical substitution to\nsrv-\u003etotal_read - srv-\u003epdu_size left an expression that is identically\nzero: standard_receive3() reads MID_HEADER_SIZE() bytes and then exactly\npdu_length - MID_HEADER_SIZE() more, adding both to total_read.\n\nlen is therefore 0, the subtraction below it wraps, and no __u32\nDataOffset can exceed the result, so the check from commit 097f5863b1a0\n(\"cifs: read overflow in is_valid_oplock_break()\") no longer rejects\nanything.  Use total_read, which is now the message length on its own.",
  "id": "CVE-2026-89630",
  "modified": "2026-09-15T03:30:38.572759917Z",
  "published": "2026-09-11T19:45:25.697Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5b16a1967a01ad4496a7206a87c3eb16f1df2b05"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ba22f575de9deeae4ae0859ca4315a7698226237"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89630.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89630"
    },
    {
      "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:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "smb: client: restore the data_offset bound in is_valid_oplock_break()"
}