CVE-2026-100888

A weakness has been identified in Trusted Domain Project OpenDKIM up to 2.11.0. This affects the function dkim_canon_selecthdrs of the file libopendkim/dkim-canon.c of the component DKIM Signature Header Selection. Executing a manipulation of the argument h can lead to out-of-bounds write. The attack can be executed remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

• https://vuldb.com/cve/CVE-2026-100888
• https://vuldb.com/submit/917015
• https://vuldb.com/vuln/410837
• https://vuldb.com/vuln/410837/cti
• https://weitongli.com/share/opendkim-h-tag-oob-write.html