CVE-2026-5071: Zephyrproject Zephyr

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

The SocketCAN implementation validates the length of a user-provided buffer containing a socketcan_frame object using only a NET_ASSERT statement in zcan_sendto_ctx() before dereferencing it in socketcan_to_can_frame(). In production builds where assertions are disabled, a userspace application that controls the length passed to a sendto syscall can supply an incomplete or truncated frame, causing socketcan_to_can_frame() to dereference fields beyond the end of the buffer. This results in an out-of-bounds read that can cause denial-of-service crashes or, because the parsed frame contents are transmitted on the network, leak adjacent memory.

Affected products

• Zephyrproject Zephyr: up to and including 4.3.0

Published 2026-05-30. Last modified 2026-07-22.