{"id":"CVE-2026-68202","revision":"b0dec163f66546cd8035b8e50e02f66a","records":[{"revision":"b0dec163f66546cd8035b8e50e02f66a","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-68202","aliases":[],"title":"ALSA: seq: close a re-opened queue timer in the destructor","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: seq: close a re-opened queue timer in the destructor\n\nqueue_delete() closes the queue timer, then frees it. snd_seq_timer_close()\nclears q->timer->timeri. snd_use_lock_sync() then drains borrowers, and\nsnd_seq_timer_delete() frees q->timer.\n\nA borrower can re-open the timer inside that window. A SET_QUEUE_CLIENT\nthat took a queueptr() use_lock reference before the queue was unlinked\nruns snd_seq_timer_open() after the close. Open refuses re-open only while\ntimeri is set, and the close just cleared it, so it re-opens timeri.\n\nsnd_seq_timer_delete() does not close that instance. Its snd_seq_timer_stop()\nis a no-op, because running was cleared first. So it frees q->timer with the\ninstance still live. The queue is freed next.\n\nThe instance stays on the global timer with callback_data pointing at the\nfreed queue. A non-owner START on the unlocked queue arms it. The next tick\nderefs the freed queue in snd_seq_timer_interrupt().\n\nReachable by an unprivileged user with access to /dev/snd/seq. No CAP and\nno queue ownership required.\n\nClose any lingering instance in the destructor. There, ->timeri can no\nlonger change: the queue is unlinked and all use_lock borrowers have\ndrained, so no snd_seq_queue_use() can re-open it. Close it before clearing\nq->timer. snd_timer_close() waits for any in-flight snd_seq_timer_interrupt()\nto finish, and that callback still reads q->timer (via snd_seq_check_queue()),\nso q->timer must stay valid until it drains.","state":0,"publishedAt":"2026-08-10T12:00:21.279+00:00","modifiedAt":"2026-10-19T20:58:57.086+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/seq/seq_timer.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"b7feeaca1f53b10df9b4de9eaf611767ca70dc92\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"7478ef94b49bc9789cf1a003deec58b42283dde4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"9d9be6fc30f384f92c4e1b8ed40bd9d4796b7833\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"fb40d03ed792a8a8bf77aa0ee15df57b0ff78b07\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"24f0cabf173539f048946c8fc221131dc221f277\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"6a10025c7fd09a7d2af37a3ae1da188569fce470\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"31a6163e301d832060f8236f1ed17cbc1ca198df\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\n                            \"lessThan\": \"2c4dc0ed50b05cd847a4b34b8cebf0775f19aeb9\",\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/seq/seq_timer.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.12\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.12\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.266\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.217\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.183\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.148\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.101\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.42\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.6\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\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/b7feeaca1f53b10df9b4de9eaf611767ca70dc92","https://git.kernel.org/stable/c/7478ef94b49bc9789cf1a003deec58b42283dde4","https://git.kernel.org/stable/c/9d9be6fc30f384f92c4e1b8ed40bd9d4796b7833","https://git.kernel.org/stable/c/fb40d03ed792a8a8bf77aa0ee15df57b0ff78b07","https://git.kernel.org/stable/c/24f0cabf173539f048946c8fc221131dc221f277","https://git.kernel.org/stable/c/6a10025c7fd09a7d2af37a3ae1da188569fce470","https://git.kernel.org/stable/c/31a6163e301d832060f8236f1ed17cbc1ca198df","https://git.kernel.org/stable/c/2c4dc0ed50b05cd847a4b34b8cebf0775f19aeb9"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68202","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-68202","identifiers":["CVE-2026-68202"]},"retained":false,"historicalAffected":[]}],"coverage":[]}