{
  "cveId": "CVE-2026-89750",
  "url": "https://patchblox.com/security/cve/CVE-2026-89750",
  "summary": "CVE-2026-89750 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-89750, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "tracing/user_events: Clear copied tracing state before fork duplication",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  tracing/user_events: Clear copied tracing state before fork duplication  dup_task_struct() copies user_event_mm from the parent into the child, without grabbing a reference to it. user_event_mm_dup() should replace it, but it leaves that copied pointer unmodified if user_event_mm_alloc() fails.  When the child exits, user_event_mm_remove() decrements a reference the child never owned, which ultimately frees user_event_mm, while the parent still as a stale pointer to it. This creates a UAF, which KASAN reports as:      BUG: KASAN: slab-use-after-free in     current_user_event_mm\u002B0x51/0x1d0 Write of size 4 at addr     ffff888005010d30 by task init/44      Call Trace:      \u003CTASK\u003E      kasan_report\u002B0xce/0x100      kasan_check_range\u002B0x10f/0x1e0      current_user_event_mm\u002B0x51/0x1d0      user_events_ioctl\u002B0x82e/0x15c0      __x64_sys_ioctl\u002B0x139/0x1c0      do_syscall_64\u002B0xce/0x450      entry_SYSCALL_64_after_hwframe\u002B0x77/0x7f      Allocated by task 44:      __kasan_kmalloc\u002B0x8f/0xa0      __kmalloc_cache_noprof\u002B0x180/0x3a0      user_event_mm_alloc\u002B0x3c/0x1f0      current_user_event_mm\u002B0x88/0x1d0      Freed by task 42:      __kasan_slab_free\u002B0x43/0x70      kfree\u002B0x13a/0x390      process_one_work\u002B0x696/0xf90      worker_thread\u002B0x420/0xba0  The fix simply clears the copied pointer before any possible failure. In case of failure, the child then has nothing to free.",
  "published": "2026-09-11T20:20:05Z",
  "severity": "Important",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00163,
  "epssPercentile": 0.05546,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-89750",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.111-1",
      "fix": "DEBIAN-CVE-2026-89750",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89750",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-89750",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89750",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "linux-6.12",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.12.111-1~deb12u1",
      "fix": "DEBIAN-CVE-2026-89750",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89750",
      "released": "2026-09-23T19:19:02Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}