CVE-2026-5588

CRITICAL

PKIX draft CompositeVerifier accepts empty signature sequence as valid.

Title source: cna

Description

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). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11.

References (2)

https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905588

[Patch] https://github.com/bcgit/bc-java/commit/656bae0dbd9b1521f840521ff786e78749fe3057

View Patch ZIP pw:eip

Scores

CVSS v4 10.0

EPSS 0.0001

EPSS Percentile 1.7%

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Details

CWE

CWE-327

Status published

Products (11)

Legion of the Bouncy Castle Inc./BC-JAVA 1.49 - 1.84

Legion of the Bouncy Castle Inc./BC-JAVA 1.67 - 1.84

Legion of the Bouncy Castle Inc./BCPKIX-FIPS 2.0.6 - 2.0.11

Legion of the Bouncy Castle Inc./BCPKIX-FIPS 2.1.7 - 2.1.11

org.bouncycastle/bcpkix-debug-jdk14 1.49 - 1.84Maven

org.bouncycastle/bcpkix-debug-jdk15to18 1.49 - 1.84Maven

org.bouncycastle/bcpkix-debug-jdk18on 1.49 - 1.84Maven

org.bouncycastle/bcpkix-jdk14 1.49 - 1.84Maven

org.bouncycastle/bcpkix-jdk15on 1.49 - 1.84Maven

org.bouncycastle/bcpkix-jdk15to18 1.49 - 1.84Maven

... and 1 more

Published Apr 15, 2026

Tracked Since Apr 15, 2026