A vulnerability described as critical has been identified in OpenSSL up to 3.0.19/3.3.6/3.4.4/3.5.5/3.6.1 . Affected by this issue is some unknown functionality of the component Hexadecimal Conversion Handler . Executing a manipulation can lead to heap-based buffer overflow. This vulnerability is handled as CVE-2026-31789 . The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.