CVE-2026-53193 (GCVE-0-2026-53193)
Vulnerability from cvelistv5
Published
2026-06-25 08:39
Modified
2026-10-19 19:57
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Forcibly close timer instances at closing When snd_timer object is freed via snd_timer_free() and still pending snd_timer_instance objects are assigned to the timer object, it tries to unlink all instances and just set NULL to each ti->timer, then releases the resources immediately. The problem is, however, when there are slave timer instances that are associated with a master instance linked to this timer: namely, those slave instances still point to the freed timer object although the master instance is unlinked, which may lead to user-after-free. The bug can be easily triggered particularly when a new userspace-driven timers (CONFIG_SND_UTIMER) is involved, since it can create and delete the timer object via a simple file open/close, while the other applications may keep accessing to that timer. This patch is an attempt to paper over the problem above: now instead of just unlinking, call snd_timer_close[_locked]() forcibly for each pending timer instance, so that all assigned slave timer instances are properly detached, too. Since snd_timer_close() might be called later by the driver that created that instance, the check of SNDRV_TIMER_IFLG_DEAD is added at the beginning, too.
References
Impacted products
Vendor Product Version
Linux Linux Version: 37745918e0e7575bc40f38da93a99b9fa6406224
Version: 37745918e0e7575bc40f38da93a99b9fa6406224
Version: 37745918e0e7575bc40f38da93a99b9fa6406224
Version: 37745918e0e7575bc40f38da93a99b9fa6406224
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