Double Free in Linux kernel - CVE-2026-23394
Published: March 25, 2026
Vulnerability identifier: #VU124443
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-23394
CWE-ID: CWE-415
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a race condition in the af_unix garbage collection mechanism when handling MSG_PEEK system calls. A local user can send a specially crafted sequence of system calls involving MSG_PEEK and socket closure to trigger incorrect garbage collection of active Unix domain sockets, leading to a denial of service.
The issue arises when MSG_PEEK increases a file reference count without synchronizing with garbage collection, causing the collector to incorrectly identify live sockets as dead and purge their receive queues.
How to mitigate CVE-2026-23394
Install security update from vendor's repository.