CVE-2026-5071 can: Local Denial of Service via SocketCAN Send
A local attacker can cause a denial of service or leak memory by sending truncated SocketCAN frames in production builds where assertions are disabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5071?
CVE-2026-5071 is a medium-severity denial of service vulnerability in Zephyrproject Zephyr, published on 30 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-125
Which versions are affected by CVE-2026-5071?
It affects 1 product.
Products include Zephyrproject Zephyr.
How do I fix CVE-2026-5071?
No fix has been published for CVE-2026-5071 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-5071 being exploited?
There is no known exploitation of CVE-2026-5071 in the wild and no public exploit code.
Other vulnerabilities in Zephyrproject Zephyr
- CVE-2026-5067 Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key
- CVE-2022-3806 Bluetooth HCI Error Handling Double Free
- CVE-2017-14199 Memory corruption in getaddrinfo
- CVE-2018-1000800 Null dereference in n/a
- CVE-2021-3329 DOS: Incorrect handling of the initial HCI ACL_MTU handshake packet leads to crash of bluetooth host layer
Sources
Also known as GHSA-c3w6-x7m3-3c58.