CVE-2026-10671

/// Technical description

In Zephyr's kernel pipe implementation, the userspace syscall verifier z_vrfy_k_pipe_init() in kernel/pipe.c used K_SYSCALL_OBJ() (which requires the kernel object to already be initialized) instead of K_SYSCALL_OBJ_NEVER_INIT() (which rejects an already-initialized object). As a result, on CONFIG_USERSPACE builds an unprivileged user thread that has been granted access to a k_pipe object can invoke the k_pipe_init syscall to re-initialize a pipe that is already in use.

z_impl_k_pipe_init() unconditionally resets the ring buffer, sets pipe->waiting to 0, and re-initializes both wait queues (z_waitq_init on pipe->data and pipe->space) without waking or accounting for threads currently blocked on the pipe. Any thread already pended in k_pipe_read()/k_pipe_write() is left orphaned: still marked pending with pended_on pointing at the cleared wait queue and with stale qnode_dlist links into the (now re-initialized) embedded list head.

When such an orphaned waiter is later timed out or wok

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References