{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f9b94daa542a8d2532f0930f01cd9aec2d19621b"
            },
            {
              "fixed": "05ebe1e1d7d38c2612bacfefe043a33572ae34cb"
            },
            {
              "fixed": "ddbe921ed16a0ad2d9e09574c3f3aabec7528325"
            },
            {
              "fixed": "7a49d19ff9baaf61217e5ec14199c18bc2d93ee4"
            },
            {
              "fixed": "372f8534244d632ad5118e8a87a11291b01712d3"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.8.0"
            },
            {
              "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-2026-89747.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix use-after-free in trace_pipe read on sub-buffer order change\n\nWriting to buffer_subbuf_size_kb calls ring_buffer_subbuf_order_set(),\nwhich frees every sub-buffer of the ring buffer, including the reader\npage, and replaces them with newly allocated ones.\n\nReaders of trace_pipe hold pointers into those pages. ring_buffer_peek()\nlooks up an event under cpu_buffer-\u003ereader_lock but returns the event\npointer after dropping the lock, and peek_next_entry() then calls\nring_buffer_event_length() and ring_buffer_event_data() on it. If the\nsub-buffer order is changed in that window, the reader dereferences\nfreed memory:\n\n  BUG: KASAN: use-after-free in ring_buffer_peek+0x3e0/0x430\n  Read of size 1 at addr ffff88802a4cf010 by task syz-executor989/6002\n\n  Freed by:\n   free_buffer_page kernel/trace/ring_buffer.c:398 [inline]\n   ring_buffer_subbuf_order_set+0x1325/0x18e0 kernel/trace/ring_buffer.c:7444\n   buffer_subbuf_size_write+0x182/0x280 kernel/trace/trace.c:8221\n\nTake trace_access_lock(RING_BUFFER_ALL_CPUS) around the order change.\nThis is the lock trace_pipe readers already hold across their entire\npeek-and-print loop, so the swap can no longer race with a reader that\nis dereferencing a peeked event.",
  "id": "CVE-2026-89747",
  "modified": "2026-09-15T03:30:45.148967700Z",
  "published": "2026-09-11T19:46:52.268Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/05ebe1e1d7d38c2612bacfefe043a33572ae34cb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/372f8534244d632ad5118e8a87a11291b01712d3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7a49d19ff9baaf61217e5ec14199c18bc2d93ee4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ddbe921ed16a0ad2d9e09574c3f3aabec7528325"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89747.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89747"
    },
    {
      "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: Fix use-after-free in trace_pipe read on sub-buffer order change"
}