CVE-2026-34155 RAUC: Improper Signing of Plain Bundles Exceeding 2 GiB
An integer overflow in RAUC allows attackers to modify unsigned portions of large update bundles, bypassing signature verification on embedded Linux systems.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-34155?
CVE-2026-34155 is a high-severity vulnerability in rauc, published on 31 Mar 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
RAUC controls the update process on embedded Linux systems. Prior to version 1.15.2, RAUC bundles using the 'plain' format exceeding a payload size of 2 GiB cause an integer overflow which results in a signature which covers only the first few bytes of the payload. Given such a bundle with a legitimate signature, an attacker can modify the part of the payload which is not covered by the signature. This issue has been patched in version 1.15.2.
Which versions are affected by CVE-2026-34155?
It affects 1 product.
Products include Pengutronix Rauc.
How do I fix CVE-2026-34155?
Upgrade to a fixed version.
Is CVE-2026-34155 being exploited?
There is no known exploitation of CVE-2026-34155 in the wild and no public exploit code.
Other vulnerabilities in rauc
Sources
Also known as DEBIAN-CVE-2026-34155, GHSA-6hj7-q844-m2hx, UBUNTU-CVE-2026-34155.