{
  "cveId": "CVE-2026-80866",
  "url": "https://patchblox.com/security/cve/CVE-2026-80866",
  "summary": "CVE-2026-80866 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-80866, released September 5, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "tipc: avoid busy looping in tipc_exit_net()",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  tipc: avoid busy looping in tipc_exit_net()  Blamed commit introduced a busy-wait loop in tipc_exit_net() to wait for pending UDP bearer cleanup works to complete:         while (atomic_read(\u0026tn-\u003Ewq_count))                cond_resched();  This loop can busy-wait for a long time if cond_resched() is a NOP. This typically happens if the netns exit is executed by a high priority task, or under kernels configured without preemption (CONFIG_PREEMPT_NONE). In such cases, it wastes CPU cycles and can lead to soft lockups.  Fix this by replacing the busy loop with wait_var_event(), allowing the thread to sleep properly until the work queue count reaches zero.  Accordingly, update cleanup_bearer() to use atomic_dec_and_test() and wake_up_var() to wake up the waiter when the count drops to zero.  This uses the global wait queue hash table, avoiding the need to bloat struct tipc_net with a wait_queue_head_t. The atomic_dec_and_test() provides the necessary memory barrier to ensure the wakeup is not missed.",
  "published": "2026-09-04T17:16:58Z",
  "severity": "Moderate",
  "cvss": 4.1,
  "epss": 0.00197,
  "epssPercentile": 0.09463,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80866",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.115-2",
      "fix": "DEBIAN-CVE-2026-80866",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80866",
      "released": "2026-09-05T01:57:10Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.1.5-1",
      "fix": "DEBIAN-CVE-2026-80866",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80866",
      "released": "2026-09-05T01:57:10Z"
    }
  ],
  "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"
  }
}