CVE Catalog

CVE-2026-10670

MediumCVSS 5.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.11%

1th percentile - higher than 1% of all known CVEs

Summary

In Zephyr RTOS, the CONFIG_USERSPACE verification handler for the k_thread_name_copy() system call calls k_object_find() on a user-supplied thread pointer and dereferences the returned struct without NULL check. If the pointer is not a registered kernel object, a NULL dereference occurs in supervisor mode, causing a system crash or reboot.

Risk Assessment

Unprivileged user code can intentionally invoke this syscall with an invalid pointer, causing a denial of service (DoS) by crashing or rebooting the kernel. The vulnerability breaks the userspace-kernel security boundary.

Recommendation

Immediately update Zephyr RTOS to a patched version (v4.4.1 or later). If updating is not possible, disable CONFIG_USERSPACE and CONFIG_THREAD_NAME in the kernel configuration.

Other vulnerabilities in Zephyr RTOS

See all
Original NVD description (English source)

The CONFIG_USERSPACE verification handler for the k_thread_name_copy() system call (z_vrfy_k_thread_name_copy() in kernel/thread.c) calls k_object_find() on the caller-supplied thread pointer and then dereferences the returned struct k_object without checking it for NULL. k_object_find() returns NULL whenever the supplied pointer is not a registered (static or dynamic) kernel object. The pre-fix guard tested thread == NULL instead of ko == NULL, so an unprivileged user-mode thread that invokes k_thread_name_copy() with any non-NULL but unregistered pointer (e.g. an arbitrary address) passes the NULL test, after which the verifier reads ko->type through a NULL pointer. Because the syscall verifier runs in supervisor mode, this NULL dereference is a kernel-mode fault that halts or reboots the system, allowing untrusted user code to crash the kernel across the userspace security boundary (denial of service). The marshaller passes the thread argument to the verifier without any prior K_SYSCALL_OBJ validation, so the bad pointer reaches the defect directly. The flaw affects builds with CONFIG_USERSPACE and CONFIG_THREAD_NAME enabled and has been present since the special-case lookup was introduced around v2.0.0; it is present in v4.4.0 and earlier. The fix changes the guard to check the k_object_find() return value (ko == NULL) before dereferencing it.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS