{"id":"CVE-2026-43437","revision":"ff7aa27ee74a42e6826e982889b10831","records":[{"revision":"ff7aa27ee74a42e6826e982889b10831","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-43437","aliases":[],"title":"ALSA: pcm: fix use-after-free on linked stream runtime in snd_pcm_drain()","description":"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->runtime at line 2157).  After\nreleasing the stream lock at line 2169, the code accesses\nruntime->no_period_wakeup, runtime->rate, and runtime->buffer_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.","state":0,"publishedAt":"2026-05-08T14:22:07.314+00:00","modifiedAt":"2026-10-19T19:26:36.663+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"sound/core/pcm_native.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"9baee36e8c5443411c4629afabafaff8a46a23fd\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"f2cb2e0d27fb925c73a78f0ce7d6dbf68d3747c1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"fc71f888994569f87d5bee20b1ac6c9c1e3a7a79\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"629cf09464cf98670996ea5c191dc9743e6f3f00\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"4a758e9a1f5ed722f83c4dd35f867fe811553bcb\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f2b3614cefb61ee6046a0aaee503ee37f227d310\",\n                            \"lessThan\": \"9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"sound/core/pcm_native.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.253\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.220\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.167\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.130\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.78\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.19\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.19.9\",\n                            \"lessThanOrEqual\": \"6.19.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/9baee36e8c5443411c4629afabafaff8a46a23fd","https://git.kernel.org/stable/c/f2cb2e0d27fb925c73a78f0ce7d6dbf68d3747c1","https://git.kernel.org/stable/c/fc71f888994569f87d5bee20b1ac6c9c1e3a7a79","https://git.kernel.org/stable/c/629cf09464cf98670996ea5c191dc9743e6f3f00","https://git.kernel.org/stable/c/ae8f8d30d334bad5b1b3cdb1eb8a0b771f55e432","https://git.kernel.org/stable/c/4a758e9a1f5ed722f83c4dd35f867fe811553bcb","https://git.kernel.org/stable/c/c2f64e05a0587a83ec42dbd6b7a7ded79b2ff694","https://git.kernel.org/stable/c/9b1dbd69ba6f8f8c69bc7b77c2ce3b9c6ed05ba6"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-43437","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-43437","identifiers":["CVE-2026-43437"]},"retained":false,"historicalAffected":[]}],"coverage":[]}