{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "af5d68f8892f8ee8f137648b79ceb2abc153a19b"
            },
            {
              "fixed": "42b3332efacfd2140be4cd0dedad4fb96b8ae90e"
            },
            {
              "fixed": "891bd8335a0de3bb15c3b797ce3026bbb0dbef6c"
            },
            {
              "fixed": "395b25968fe854d4efaa19a8e9b7a5b6d1b3eea3"
            },
            {
              "fixed": "a92193c91e8839fe5fc209616ea95465ae4b919d"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.9.0"
            },
            {
              "fixed": "6.12.113"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.56"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98858.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix task_work add use-after-free with SQPOLL\n\nFor SQPOLL, the sqpoll thread runs task_work off its own list and\ndoesn't need to be told about it, so it can pop and complete a request\nas soon as mpscq_push() has published it. If that was the last request\nholding the ring alive, io_ring_exit_work() then frees the ctx, stops\nthe thread, and with it the tctx, while io_req_normal_work_add() is\nstill looking at both after the push:\n\n  BUG: KASAN: slab-use-after-free in io_req_normal_work_add+0x439/0x510\n  Read of size 4 at addr ff11000000ca0000 by task repro/55\n  (...)\n  BUG: KASAN: slab-use-after-free in queue_work_on+0x25/0x70\n  Write of size 8 at addr ff11000000c3bd00 by task repro/55\n\nHold an RCU read lock across the add, like io_req_local_work_add() already\ndoes, and have io_ring_exit_work() wait for a grace period for SQPOLL rings\nas well before freeing the ctx.",
  "id": "CVE-2026-98858",
  "modified": "2026-10-19T02:30:29.153947557Z",
  "published": "2026-10-18T15:51:19.578Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/395b25968fe854d4efaa19a8e9b7a5b6d1b3eea3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/42b3332efacfd2140be4cd0dedad4fb96b8ae90e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/891bd8335a0de3bb15c3b797ce3026bbb0dbef6c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a92193c91e8839fe5fc209616ea95465ae4b919d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98858.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98858"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "io_uring: fix task_work add use-after-free with SQPOLL"
}