Memory leak in Linux kernel - CVE-2026-74543

Vulnerability identifier: #VU143241

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74543

CWE-ID: CWE-401

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local attacker to cause a denial of service.

The vulnerability exists due to a memory leak in udp_tunnel_nic_unregister() when handling failed device registration and netdevice unregister events. A local attacker can trigger device registration failure with queued work to cause a denial of service.

The issue occurs because a queued work item can cause the unregister path to return early, leaving a struct udp_tunnel_nic allocation permanently leaked.

Linux kernel
Debian Linux
openEuler
kernel-headers
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-extra-modules
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-headers - update to 6.6.0-145.3.31.162
python3-perf-debuginfo - update to 6.6.0-145.3.31.162
python3-perf - update to 6.6.0-145.3.31.162
perf-debuginfo - update to 6.6.0-145.3.31.162
perf - update to 6.6.0-145.3.31.162
kernel-tools-devel - update to 6.6.0-145.3.31.162
kernel-tools-debuginfo - update to 6.6.0-145.3.31.162
kernel-tools - update to 6.6.0-145.3.31.162
kernel-source - update to 6.6.0-145.3.31.162
kernel-extra-modules - update to 6.6.0-145.3.31.162
kernel-devel - update to 6.6.0-145.3.31.162
kernel-debugsource - update to 6.6.0-145.3.31.162
kernel-debuginfo - update to 6.6.0-145.3.31.162
bpftool-debuginfo - update to 6.6.0-145.3.31.162
bpftool - update to 6.6.0-145.3.31.162
kernel - update to 6.6.0-145.3.31.162
linux (Debian package) - update to 6.12.105-1

• https://git.kernel.org/stable/c/080695e6f005e2396f1207fd69d24c442cb230c6
• https://git.kernel.org/stable/c/b322532a4b774db1b480a2de84125910a70739a5
• https://git.kernel.org/stable/c/b712da45bd9b9835d132e9fbc0c3e43c164cb1fd
• https://git.kernel.org/stable/c/f82a2ded3d7a9098267c84f14eafdb98c4550ac5

• Memory leak in Linux kernel ipv4
• Debian update for linux
• openEuler 24.03 LTS SP3 update for kernel