{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f2b3614cefb61ee6046a0aaee503ee37f227d310"
            },
            {
              "fixed": "9baee36e8c5443411c4629afabafaff8a46a23fd"
            },
            {
              "fixed": "fc71f888994569f87d5bee20b1ac6c9c1e3a7a79"
            },
            {
              "fixed": "629cf09464cf98670996ea5c191dc9743e6f3f00"
            },
            {
              "fixed": "ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432"
            },
            {
              "fixed": "4a758e9a1f5ed722f83c4dd35f867fe811553bcb"
            },
            {
              "fixed": "c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694"
            },
            {
              "fixed": "9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "6.1.167"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.130"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.78"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.19"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43437.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: pcm: fix use-after-free on linked stream runtime in snd_pcm_drain()\n\nIn the drain loop, the local variable 'runtime' is reassigned to a\nlinked stream's runtime (runtime = s-\u003eruntime at line 2157).  After\nreleasing the stream lock at line 2169, the code accesses\nruntime-\u003eno_period_wakeup, runtime-\u003erate, and runtime-\u003ebuffer_size\n(lines 2170-2178) — all referencing the linked stream's runtime without\nany lock or refcount protecting its lifetime.\n\nA concurrent close() on the linked stream's fd triggers\nsnd_pcm_release_substream() → snd_pcm_drop() → pcm_release_private()\n→ snd_pcm_unlink() → snd_pcm_detach_substream() → kfree(runtime).\nNo synchronization prevents kfree(runtime) from completing while the\ndrain path dereferences the stale pointer.\n\nFix by caching the needed runtime fields (no_period_wakeup, rate,\nbuffer_size) into local variables while still holding the stream lock,\nand using the cached values after the lock is released.",
  "id": "CVE-2026-43437",
  "modified": "2026-07-15T01:49:20.014302212Z",
  "published": "2026-05-08T14:22:07.314Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4a758e9a1f5ed722f83c4dd35f867fe811553bcb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/629cf09464cf98670996ea5c191dc9743e6f3f00"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9baee36e8c5443411c4629afabafaff8a46a23fd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fc71f888994569f87d5bee20b1ac6c9c1e3a7a79"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43437.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43437"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "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: fix use-after-free on linked stream runtime in snd_pcm_drain()"
}