What is CVE-2026-12234?

CVE-2026-12234 is a high-severity vulnerability in Zephyrproject Zephyr, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.8/10. Published 2026-08-12.

How severe is CVE-2026-12234?

High severity. CVSS v3 base score is 7.8 out of 10.

Vulnerability in Zephyrproject Zephyr

CVE-2026-12234

The userspace syscall verifiers z_vrfy_zsock_sendmsg() and z_vrfy_zsock_recvmsg() in subsys/net/lib/sockets/sockets.c snapshot the caller-supplied struct net_msghdr into a kernel-side copy with k_usermode_from_copy(), but then re-read the…

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Zephyrproject Zephyr — versions 2.3.0

Weakness classification (CWE)

CWE-367 — Time-of-check Time-of-use (TOCTOU) Race Condition

References

vulnerabilities@zephyrproject.org (patch)
vulnerabilities@zephyrproject.org

Frequently asked questions

What is CVE-2026-12234?: CVE-2026-12234 is a high-severity vulnerability in Zephyrproject Zephyr, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 7.8/10. Published 2026-08-12.
How severe is CVE-2026-12234?: High severity. CVSS v3 base score is 7.8 out of 10.