{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "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+0x51/0x1d0 Write of size 4 at addr     ffff888005010d30 by task init/44      Call Trace:      \u003cTASK\u003e      kasan_report+0xce/0x100      kasan_check_range+0x10f/0x1e0      current_user_event_mm+0x51/0x1d0      user_events_ioctl+0x82e/0x15c0      __x64_sys_ioctl+0x139/0x1c0      do_syscall_64+0xce/0x450      entry_SYSCALL_64_after_hwframe+0x77/0x7f      Allocated by task 44:      __kasan_kmalloc+0x8f/0xa0      __kmalloc_cache_noprof+0x180/0x3a0      user_event_mm_alloc+0x3c/0x1f0      current_user_event_mm+0x88/0x1d0      Freed by task 42:      __kasan_slab_free+0x43/0x70      kfree+0x13a/0x390      process_one_work+0x696/0xf90      worker_thread+0x420/0xba0  The fix simply clears the copied pointer before any possible failure. In case of failure, the child then has nothing to free.",
  "id": "DEBIAN-CVE-2026-89750",
  "modified": "2026-09-15T08:47:23.919432491Z",
  "published": "2026-09-11T20:20:05.883Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-89750"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-89750"
  ]
}