{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "7235759084a4f8524a46bd2638885ff3b34ce279"
            },
            {
              "fixed": "33ce55b368b64d65941867add00e7f288cbb8234"
            },
            {
              "fixed": "63b39e49a4c9d68e010e96b26fc7374f0864f2b1"
            },
            {
              "fixed": "25a0758cf6bdbfddac2be71124c9bd0692f4b0b1"
            },
            {
              "fixed": "b799f67119aff179719a0b1e12441ebbdaaf62f9"
            },
            {
              "fixed": "390f6bd8583d177029d9df4bea6667509e55a765"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.4.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "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-2026-89750.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/user_events: Clear copied tracing state before fork duplication\n\ndup_task_struct() copies user_event_mm from the parent into the child,\nwithout grabbing a reference to it. user_event_mm_dup() should\nreplace it, but it leaves that copied pointer unmodified if\nuser_event_mm_alloc() fails.\n\nWhen the child exits, user_event_mm_remove() decrements a reference\nthe child never owned, which ultimately frees user_event_mm, while\nthe parent still as a stale pointer to it. This creates a UAF, which\nKASAN reports as:\n\n    BUG: KASAN: slab-use-after-free in\n    current_user_event_mm+0x51/0x1d0 Write of size 4 at addr\n    ffff888005010d30 by task init/44\n\n    Call Trace:\n     \u003cTASK\u003e\n     kasan_report+0xce/0x100\n     kasan_check_range+0x10f/0x1e0\n     current_user_event_mm+0x51/0x1d0\n     user_events_ioctl+0x82e/0x15c0\n     __x64_sys_ioctl+0x139/0x1c0\n     do_syscall_64+0xce/0x450\n     entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\n    Allocated by task 44:\n     __kasan_kmalloc+0x8f/0xa0\n     __kmalloc_cache_noprof+0x180/0x3a0\n     user_event_mm_alloc+0x3c/0x1f0\n     current_user_event_mm+0x88/0x1d0\n\n    Freed by task 42:\n     __kasan_slab_free+0x43/0x70\n     kfree+0x13a/0x390\n     process_one_work+0x696/0xf90\n     worker_thread+0x420/0xba0\n\nThe fix simply clears the copied pointer before any possible failure.\nIn case of failure, the child then has nothing to free.",
  "id": "CVE-2026-89750",
  "modified": "2026-09-16T03:30:44.108452738Z",
  "published": "2026-09-11T19:46:54.565Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/25a0758cf6bdbfddac2be71124c9bd0692f4b0b1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/33ce55b368b64d65941867add00e7f288cbb8234"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/390f6bd8583d177029d9df4bea6667509e55a765"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/63b39e49a4c9d68e010e96b26fc7374f0864f2b1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b799f67119aff179719a0b1e12441ebbdaaf62f9"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89750.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89750"
    },
    {
      "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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "tracing/user_events: Clear copied tracing state before fork duplication"
}