{"cve":"CVE-2026-90198","nvd":{"published":"2026-09-17T17:17:14.633","modified":"2026-10-19T09:19:09.800","status":"Received","description":"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-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>","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/03c5dabc8f16bc212a5b26d2425c03a55e55a86d","https://git.kernel.org/stable/c/09b27dd01b98480334c10bf6fb8d41d5fb063a4b","https://git.kernel.org/stable/c/5ae1a690c522fea2900ff56c8c2ace7b059f5e04","https://git.kernel.org/stable/c/6da22efb5cf490b06ffbca32b10fc8af7654fee0","https://git.kernel.org/stable/c/7d9b5e86775fa97a487da08b9aa76e1674bf8868"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90198","score":0.00227,"percentile":0.13372,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}