CVE-2026-34960 barebox Out-of-Bounds Read in DHCP Option Parsing

High 7.1 Published 11 May 2026 Updated 18 Jul 2026

An attacker on the same network can crash the barebox bootloader by sending a malformed DHCP packet, requiring an upgrade to fix.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-34960?

CVE-2026-34960 is a high-severity denial of service vulnerability in barebox, published on 11 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

barebox prior to version 2026.04.0 contains an out-of-bounds read vulnerability in DHCP option parsing within the dhcp_message_type() function that fails to verify the options pointer remains within received packet bounds. An attacker on the same broadcast domain can send a crafted DHCP Offer or ACK packet without a proper 0xff end marker to cause the parser to read past valid packet data and potentially crash the system.

Weakness: CWE-125

Which versions are affected by CVE-2026-34960?

It affects 1 product.

Products include Pengutronix Barebox.

How do I fix CVE-2026-34960?

No fix has been published for CVE-2026-34960 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-2026-34960 being exploited?

There is no known exploitation of CVE-2026-34960 in the wild and no public exploit code.

Sources

Also known as GHSA-fqhc-8hwj-969h.