Race condition in Linux kernel - CVE-2026-74668

Vulnerability identifier: #VU144796

CSH Severity: Low

CVSS v4: 6.8 [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]

CVE-ID: CVE-2026-74668

CWE-ID: CWE-362

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to an inconsistent use of hard_header_len in the tpacket_snd() transmit ring send path in net/packet/af_packet.c when processing tx ring frames during packet transmission. A local user can trigger concurrent netdevice reconfiguration and send crafted ring frames to cause a denial of service.

The issue can make the reserved headroom smaller than the amount later pushed, or make the computed copy length negative.

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/016763e829cac37b3234eace86fd0a4c560de4a7
• https://git.kernel.org/stable/c/21b5953e7494c16a42e6cd8cf110e18d13ae4a6b
• https://git.kernel.org/stable/c/27e068d1b35dbec10a3cf268887c94407be4badc
• https://git.kernel.org/stable/c/d48ea5c9c4c34dc0df621f0e39ed3a16b644621a
• https://git.kernel.org/stable/c/d85d2fd54e901637c81d847811e03c662aee13cd

• Race condition in Linux kernel packet
• Debian update for linux
• openEuler 24.03 LTS SP3 update for kernel