Double Free in Linux kernel - CVE-2026-23394
Published: March 25, 2026
Vulnerability details
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.
Affected software
Debian Linux
Ubuntu
openEuler
python3-perf-debuginfo
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
kernel-source
kernel-extra-modules
linux-fips (Ubuntu package)
linux (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux (Debian package)
linux-oracle-6.17 (Ubuntu package)
linux-nvidia-6.17 (Ubuntu package)
How to mitigate CVE-2026-23394
python3-perf-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
bpftool - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
bpftool-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-debugsource - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-devel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-headers - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools-devel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
perf - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
perf-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
python3-perf - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-source - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-extra-modules - update to 6.6.0-145.0.2.143
linux-fips (Ubuntu package) - update to 6.8.0-116.116+fips1
linux (Ubuntu package) - addressed in versions 6.8.0-117.117, 6.8.0-117.117.1, 6.8.0-117.117.1~22.04.1, 6.8.0-1041.44, 6.8.0-1054.60, 6.8.0-1055.56, 6.8.0-1055.56~22.04.1, 6.8.0-1055.58+fips1, 6.8.0-1056.60, 6.8.0-1058.61, 6.8.0-1058.61+fips1, 6.8.0-2045.46, 6.8.1-1051.52, 6.8.1-1051.52~22.04.1, 6.17.0-29.29, 6.17.0-29.29~24.04.1, 6.17.0-1013.15, 6.17.0-1013.15~24.04.1, 6.17.0-1014.14, 6.17.0-1015.15, 6.17.0-1017.17, 6.17.0-1023.23
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1024.24
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1054.57, 6.8.0-1054.57.1
linux-nvidia-6.8 (Ubuntu package) - update to 6.8.0-1054.57~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1056.62, 6.17.0-1015.15, 6.17.0-1015.15~24.04.1
linux (Debian package) - update to 6.12.94-1
linux-oracle-6.17 (Ubuntu package) - update to 6.17.0-1014.14~24.04.1
linux-nvidia-6.17 (Ubuntu package) - update to 6.17.0-1026.26
External References
Related Security Bulletins
- Double Free in Linux kernel unix
- openEuler 24.03 LTS SP2 update for kernel
- openEuler 24.03 LTS SP1 update for kernel
- openEuler 24.03 LTS update for kernel
- Ubuntu update for linux
- Ubuntu update for linux
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-oracle-6.17
- Ubuntu update for linux-fips
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-nvidia-6.8
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure
- Debian update for linux
- Ubuntu update for linux-nvidia-6.17