RAUC, a firmware update manager for embedded Linux, suffers from an integer overflow when processing plain‑format bundles larger than 2 GiB. The overflow limits the generated signature to only the first few bytes of the payload, so that the remainder of the bundle is not integrity‑checked. An attacker who can supply a malicious bundle can therefore alter the unchecked part of the firmware, violating the authenticity guarantee of the update process. The flaw maps to cryptographic integrity failure (CWE‑196) and numeric value overflow (CWE‑347).

This vulnerability affects Pengutronix RAUC versions prior to 1.15.2 that are used on embedded Linux platforms. Any system deploying a bundle signed with those versions is at risk. The upstream patch in release 1.15.2 and later resolves the issue.

With a CVSS score of 7.2 the flaw is considered high severity, but an EPSS probability of less than 1 % indicates it is not widely exploited in the wild. The vulnerability is not listed in the CISA KEV catalog, reinforcing the low observed exploitation risk. Successful exploitation requires an attacker who can supply a bundle through the device’s update channel, such as via a compromised update server, supply‑chain tampering, or physical access to the update mechanism. Once the modified bundle is installed, the device may run altered firmware or experience service disruption.