bouncycastle: BC-JAVA: PKIX draft CompositeVerifier accepts empty signature sequence as valid

A flaw was found in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix. The PKIX draft CompositeVerifier implementation improperly accepts an empty signature sequence as a valid cryptographic signature. This issue allows a remote attacker to bypass signature verification mechanisms, potentially...

CVE-2026-5588

Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all pkix modules, Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All pkix modules, Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All pkix modules. This vulnerability...

CVE-2026-5588

The Bouncy Castle cryptographic library (specifically the bcpkix modules) contains a vulnerability where the PKIX draft CompositeVerifier incorrectly accepts an empty signature sequence as valid. This is categorized as a Use of a Broken or Risky Cryptographic Algorithm vulnerability. The issue is...