Vulnerability in DENX Software Engineering Das U-Boot

[ Why it matters ]Priority signals

• Critical severity: CVSS 9.0

[ Description ]Official description

Das U-Boot with CONFIG_IP_DEFRAG=y parameter fails to clear IP reassembly state after delivering a complete datagram. An attacker who can deliver fragmented IP traffic can execute arbitrary code by sending duplicated last-fragment IP packets. This issue was fixed in commit b1aec609bb5e0d08c25c888c91935287ab4ee5fa in version 2026.07.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund28 Sep 2026WID-SEC-2026-3631

  DENX U-Boot: Vulnerability allows code execution Translated from German

  CVE-2026-15390

[ References ]References

• cert.pl/en/posts/2026/09/CVE-2026-15390
• source.denx.de/u-boot/u-boot/-/commit/b1aec609bb5e0d08c25c888c91935287ab4ee5fa