Use-after-free in FreeBSD - CVE-2026-49417
Published: June 11, 2026
Vulnerability identifier: #VU134368
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-49417
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: FreeBSD Foundation
Affected software:
FreeBSD
FreeBSD
Detailed vulnerability description
The vulnerability allows a local user to read and write kernel memory.
The vulnerability exists due to a use-after-free in the sound(4) mmap path when a mapped audio buffer remains accessible after the device is closed. A local user can keep using the stale mapping after closing the device to read and write kernel memory.
On systems with an audio device, the /dev/dsp device nodes are world-accessible by default.
How to mitigate CVE-2026-49417
Install security update from vendor's website.