10.0
CRITICAL CVSS 4.0
CVE-2026-5588
PKIX draft CompositeVerifier accepts empty signature sequence as valid.
Description

: Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules). PKIX draft CompositeVerifier accepts empty signature sequence as valid. This issue affects BC-JAVA: from 1.49 before 1.84.

INFO

Published Date :

April 15, 2026, 9:06 a.m.

Last Modified :

April 15, 2026, 9:06 a.m.

Remotely Exploit :

Yes !

Source :

bcorg
Affected Products

The following products are affected by CVE-2026-5588 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 CRITICAL 91579145-5d7b-4cc5-b925-a0262ff19630
Solution
Update the BC-JAVA library to a version that addresses the cryptographic validation issue.
  • Update BC-JAVA library to version 1.84 or later.
  • Verify cryptographic validation logic.
  • Apply vendor-provided patches if available.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-5588 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.