{
  "cveId": "CVE-2026-98289",
  "url": "https://patchblox.com/security/cve/CVE-2026-98289",
  "summary": "CVE-2026-98289 is fixed in 20 products on 1 platform, first by DEBIAN-CVE-2026-98289, released October 6, 2026. It is not reported as exploited. Patch Radar priority: Urgent.",
  "title": "af_unix: Unify scc_index when finalising SCC in __unix_walk_scc().",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  af_unix: Unify scc_index when finalising SCC in __unix_walk_scc().  Commit bfdb01283ee8 (\u0022af_unix: Assign a unique index to SCC.\u0022) changed Tarjan\u0027s algorithm to update lowlink with lowlink, which is called lowpoint (unix_vertex.scc_index).  unix_vertex_dead() assumes all vertices in an SCC share the same lowpoint, but this is not always true if an SCC has two or more back edges, depending on the order of DFS.  For example, the graph below has two back edges from B to A and from C to B.    A --\u003E B --\u003E C   ^    | ^    |   \u0060----\u0027 \u0060----\u0027  If DFS walks through A -\u003E B -\u003E C -\u003E B (-\u003E C -\u003E B) -\u003E A (-\u003E B -\u003E A), each index and scc_index will be updated as follows.    A --\u003E B --\u003E C    C = (3, 3)  (index, scc_index)                    B = (2, 2)                    A = (1, 1)    A ... B ... C    C = (3, 2)\u003C-.          ^    |    B = (2, 2) -\u0027          \u0060----\u0027    A = (1, 1)    A ... B ... C    C = (3, 2)   ^    | .    .    B = (2, 1)\u003C-.   \u0060----\u0027  ....     A = (1, 1) -\u0027  Then, unix_vertex_dead() thinks that B is passed to another SCC with scc_index 2, and the SCC is not garbage-collected.  This does not happen if DFS walks in a different order below or starts from B.      1      3   A --\u003E B --\u003E C   ^    | ^    |   \u0060----\u0027 \u0060----\u0027      2      4  Let\u0027s unify scc_index across the SCC when finalising it.  Note that updating v-\u003Eindex was previously done in unix_scc_dead(), when called from __unix_walk_scc(), just to save one loop.  Since __unix_walk_scc() now iterates over the SCC anyway, the update is moved back to __unix_walk_scc() and \u0027fast\u0027 argument is dropped.",
  "published": "2026-10-06T09:18:19Z",
  "severity": "Critical",
  "cvss": 9.8,
  "epss": 0.00166,
  "epssPercentile": 0.05858,
  "priority": "Urgent",
  "priorityTier": 2,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98289",
  "fixes": [
    {
      "platform": "linux",
      "product": "bpftool6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "bpftool6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-6.18.54-121.166",
      "release": "amzn 2023",
      "fixedVersion": "1:1.0-0.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-aarch64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-x86_64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-headers",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra-common",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.8-1",
      "fix": "DEBIAN-CVE-2026-98289",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-98289",
      "released": "2026-10-06T21:56:27Z"
    },
    {
      "platform": "linux",
      "product": "microvm-kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}