{"id":"CVE-2026-90198","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: core: Fix use-after-free in snd_card_do_free()\n\nA use-after-free was detected in snd_card_do_free() when a sound card\nmanaged by devres is unbound while a user-sp…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: core: Fix use-after-free in snd_card_do_free()\n\nA use-after-free was detected in snd_card_do_free() when a sound card\nmanaged by devres is unbound while a user-sp…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < d3d67f680dbc23a5e5e3d3ecfdbf700465809877","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < 09b27dd01b98480334c10bf6fb8d41d5fb063a4b","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < 03c5dabc8f16bc212a5b26d2425c03a55e55a86d","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < 6da22efb5cf490b06ffbca32b10fc8af7654fee0","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < a561012868ae37c28f61fdf658bf6f251bc0e8e8","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < 7d9b5e86775fa97a487da08b9aa76e1674bf8868","Linux >= e8ad415b7a55cb9a9fbfc04696518d5ea0b609b3 < 5ae1a690c522fea2900ff56c8c2ace7b059f5e04","Linux 5.15"],"published":"2026-09-17","updated":"2026-09-17","sourceUpdated":"2026-09-17T17:17:14.633","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90198","references":[{"url":"https://git.kernel.org/stable/c/03c5dabc8f16bc212a5b26d2425c03a55e55a86d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/09b27dd01b98480334c10bf6fb8d41d5fb063a4b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5ae1a690c522fea2900ff56c8c2ace7b059f5e04","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6da22efb5cf490b06ffbca32b10fc8af7654fee0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7d9b5e86775fa97a487da08b9aa76e1674bf8868","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a561012868ae37c28f61fdf658bf6f251bc0e8e8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d3d67f680dbc23a5e5e3d3ecfdbf700465809877","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-17T16:21:47.861Z","epss":0.00221,"epssPercentile":0.12912,"slug":"CVE-2026-90198","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nALSA: core: Fix use-after-free in snd_card_do_free()\n\nA use-after-free was detected in snd_card_do_free() when a sound card\nmanaged by devres is unbound while a user-space application still holds an\nopen file descriptor.\n\nFor managed cards, the memory is allocated using devres_alloc(), and its\nrelease function is set to __snd_card_release(), which calls\nsnd_card_free(). When the device is unbound, the unbind thread calls\nsnd_card_free(), which drops a reference to the card's device. If the user\nthread still has an open file descriptor, the reference count does not\nreach zero, and the unbind thread blocks on wait_for_completion(&released).\n\nWhen the user thread closes the file descriptor, it drops the final\nreference, invoking the device release callback release_card_device(),\nwhich calls snd_card_do_free(). snd_card_do_free() performs cleanup and\ncalls complete(card->release_completion). This wakes up the unbind thread,\nwhich returns from snd_card_free() and __snd_card_release(). The devres\ncore then immediately frees the memory block containing the snd_card\nstructure.\n\nMeanwhile, the user thread continues execution in snd_card_do_free() and\nevaluates `if (!card->managed)`. It reads the `managed` boolean from the\nsnd_card structure that was just freed by the unbind thread, triggering a\nKASAN use-after-free.\n\nFix this by caching the value of card->managed in a local variable before\ncalling complete(). This ensures that the card pointer is not dereferenced\nafter the unbind thread has been woken up and potentially freed the card.\n\nBUG: KASAN: use-after-free in snd_card_do_free sound/core/init.c:604\n[inline]\nBUG: KASAN: use-after-free in release_card_device+0x1ab/0x1b0\nsound/core/init.c:153\nRead of size 1 at addr ffff8881912ec909 by task syz-executor130/5857\n\nCall Trace:\n <TASK>\n dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120\n print_address_description+0x55/0x1e0 mm/kasan/report.c:378\n print_report+0x58/0x70 mm/kasan/report.c:482\n kasan_report+0x117/0x150 mm/kasan/report.c:595\n snd_card_do_free sound/core/init.c:604 [inline]\n release_card_device+0x1ab/0x1b0 sound/core/init.c:153\n device_release+0xc4/0x1f0 drivers/base/core.c:-1\n kobject_cleanup lib/kobject.c:689 [inline]\n kobject_release lib/kobject.c:720 [inline]\n kref_put include/linux/kref.h:65 [inline]\n kobject_put+0x222/0x550 lib/kobject.c:737\n snd_card_file_remove+0x331/0x390 sound/core/init.c:1125\n snd_pcm_release+0x12c/0x160 sound/core/pcm_native.c:2986\n __fput+0x418/0xa50 fs/file_table.c:512\n fput_close_sync+0x11f/0x240 fs/file_table.c:617\n __do_sys_close fs/open.c:1511 [inline]\n __se_sys_close fs/open.c:1496 [inline]\n __x64_sys_close+0x7e/0x110 fs/open.c:1496\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n </TASK>\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}