Quick answers
- Is CVE-2026-99271 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-99271 being exploited in the wild.
- How severe is CVE-2026-99271?
- Informational severity, published 7 November 2026.
- Which products and versions are affected?
- Linux Kernel versions before fix (unspecified).
- Is there a fix for CVE-2026-99271?
- Yes: fixed in Fixed by clearing prev_fbuf and prev_fsize in line6_buffer_release(). Until then: Avoid closing capture streams on Line 6 USB audio devices while playback is active, or do not enable impulse test signal generation on potentially untrusted systems. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-99271 attacked?
- It is attacked with local access, in an operating system.
- Am I affected by CVE-2026-99271?
- Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: Fixed by clearing prev_fbuf and prev_fsize in line6_buffer_release()
Avoid closing capture streams on Line 6 USB audio devices while playback is active, or do not enable impulse test signal generation on potentially untrusted systems.
Technical details
A slab-use-after-free read occurs in submit_audio_out_urb() when the playback code dereferences a stale pointer (prev_fbuf) to a freed capture buffer. The vulnerability exists because line6_buffer_release() frees the capture stream buffer without clearing the prev_fbuf pointer that is accessed during audio playback. This requires local access to control audio devices and specific timing to trigger.
Affected products
- Linux Linux kernel versions before fix (unspecified)
Timeline
- 2026-11-07: disclosed