CVE-2026-101308 TOCTOU race between sound(4) buffer resizing and mmap
A race condition in the FreeBSD sound driver allows local attackers to trigger a use-after-free and escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-101308?
CVE-2026-101308 is a medium-severity vulnerability in Freebsd Freebsd, published on 15 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
When an audio channel's buffer needs to be resized, the sound(4) driver checks that the buffer is not memory-mapped and then drops the channel lock to allocate a new buffer. An mmap(2) call on another thread can complete during this window, after which the resize path frees the now-mapped buffer without rechecking.
An unprivileged local user with access to a sound device can exploit this race to trigger a use-after-free in the kernel, potentially escalating privileges.
Weakness: CWE-367
Which versions are affected by CVE-2026-101308?
It affects 1 product.
Products include Freebsd Freebsd.
How do I fix CVE-2026-101308?
No fix has been published for CVE-2026-101308 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-101308 being exploited?
There is no known exploitation of CVE-2026-101308 in the wild and no public exploit code.
Other vulnerabilities in Freebsd Freebsd
Sources
Also known as GHSA-pmrj-w7pv-p57q.