{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "92ee3c60ec9fe64404dc035e7c41277d74aa26cb"
            },
            {
              "fixed": "cbc7ec97601d09b74e05e44470fa6b0bcdabf3f5"
            },
            {
              "fixed": "fd137bf8149bc6460f9b7b1fc292025da04cb9ee"
            },
            {
              "fixed": "8c1882dfee8f404d118020664b73eb4592172226"
            },
            {
              "fixed": "9b110a9dcecc59516c77cb3c0caf1f492f75df2d"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "a42aa926843acca96c0dfbde2e835b8137f2f092"
            },
            {
              "last_affected": "9cb6c40a6ebe4a0cfc9d6a181958211682cffea9"
            },
            {
              "last_affected": "fbeb492694ce0441053de57699e1e2b7bc148a69"
            },
            {
              "last_affected": "0f6947f5f5208f6ebd4d76a82a4757e2839a23f8"
            },
            {
              "last_affected": "33061d0fba51d2bf70a2ef9645f703c33fe8e438"
            },
            {
              "last_affected": "0090c13cbbdffd7da079ac56f80373a9a1be0bf8"
            },
            {
              "last_affected": "1bbf82d9f961414d6c76a08f7f843ea068e0ab7b"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.14.279"
            },
            {
              "fixed": "4.15"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.19.243"
            },
            {
              "fixed": "4.20"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.4.193"
            },
            {
              "fixed": "5.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.10.109"
            },
            {
              "fixed": "5.11"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.15.32"
            },
            {
              "fixed": "5.16"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.16.18"
            },
            {
              "fixed": "5.17"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.17.1"
            },
            {
              "fixed": "5.18"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.18.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98116.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF\n\nsnd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation\nwith an mmap_count check performed under the PCM stream lock, but the\nlock is released long before the buffer is actually freed:\nsnd_pcm_sync_stop(), constraint refinement and do_free_pages() all\nhappen in between.  snd_pcm_mmap_data(), on the other hand, takes no\nlock at all: it validates against the old buffer's state and\ndma_bytes, remaps its pages into the VMA, and only then increments\nmmap_count.\n\nA concurrent mmap() can therefore slip in between the check and the\nfree.  remap_pfn_range() installs writable PTEs for the old buffer's\npages without taking page references, and the subsequent\ndo_free_pages() returns those pages to the page allocator while the\nVMA still maps them.  This leaves a stale, writable mapping of freed\npages: a page-level use-after-free that can be leveraged for local\nprivilege escalation.\n\nMake snd_pcm_mmap_data() participate in the buffer-access scheme\nintroduced for hw_params/hw_free: acquire runtime-\u003ebuffer_accessing\nbefore validating and remapping, and release it afterwards.  Buffer\nreallocation already fails with -EBUSY while accessors are active,\nand the mmap side now fails with -EBUSY while a reallocation is in\nprogress, so the validate/remap sequence and the check/free sequence\ncan no longer interleave.\n\nA reproducer that turns this race into a stale writable mapping of\nthe freed DMA buffer pages is available on request.",
  "id": "CVE-2026-98116",
  "modified": "2026-09-27T03:30:22.236347725Z",
  "published": "2026-09-25T10:36:01.723Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8c1882dfee8f404d118020664b73eb4592172226"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9b110a9dcecc59516c77cb3c0caf1f492f75df2d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cbc7ec97601d09b74e05e44470fa6b0bcdabf3f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fd137bf8149bc6460f9b7b1fc292025da04cb9ee"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98116.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98116"
    },
    {
      "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": "ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF"
}