CVE-2026-53193

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/586b219a22b1032b28b8bd356b963276c5e5bf53
https://git.kernel.org/stable/c/60e73ab87b84bbd6bd7ddd1d16019a3a3705ab8f
https://git.kernel.org/stable/c/da3039e91d1f835874ed6e9a33ea19ee80c2cb92
https://git.kernel.org/stable/c/f46093dd22969037beb1fce2e043f3236be41c92

Configurations

No configuration.

History

28 Jun 2026, 08:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8

25 Jun 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 09:16

Updated : 2026-06-30 14:44

NVD link : CVE-2026-53193

Mitre link : CVE-2026-53193

CVE.ORG link : CVE-2026-53193

JSON object : View

Products Affected

No product.

CWE

No CWE.

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