{
  "cveId": "CVE-2026-89641",
  "url": "https://patchblox.com/security/cve/CVE-2026-89641",
  "summary": "CVE-2026-89641 is fixed in 20 products on 1 platform, first by DEBIAN-CVE-2026-89641, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  cifs: clear tcon after cifsFileInfo_put() in cif...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  cifs: clear tcon after cifsFileInfo_put() in cifs_file_set_size()  When the else branch of cifs_file_set_size() finds a writable file handle via find_writable_file(), it borrows tcon and server from the handle\u0027s tlink, attempts the handle-based set_file_size() RPC, and then releases the handle with cifsFileInfo_put().  If set_file_size() fails, execution falls through to the path-based fallback, which reuses the borrowed tcon and server under the \u0022if (tcon == NULL)\u0022 guard.  Since tcon is not NULL at that point, the guard is skipped.  If cifsFileInfo_put() dropped the last reference on a tlink that was already removed from the tlink tree (TCON_LINK_IN_TREE cleared, as happens during reconnection or session teardown), cifs_put_tlink() will have freed tcon; the subsequent set_path_size() call is then a use-after-free.  Setting tcon = NULL after cifsFileInfo_put() causes the existing guard to take the cifs_sb_tlink() path, which acquires a fresh reference for the path-based operation or fails cleanly if the session is gone.",
  "published": "2026-09-11T20:19:49Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.0014,
  "epssPercentile": 0.03367,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "bpftool6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "bpftool6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-6.18.51-120.162",
      "release": "amzn 2023",
      "fixedVersion": "1:1.0-0.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-aarch64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-x86_64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-headers",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra-common",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-89641",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89641",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "microvm-kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
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      "product": "perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T00:53:09Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}