Home/CVE/Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all
CVE

CVE-2026-5588

Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all

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 is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84.

BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11.

BCPIX-LTS: from 2.73.7 before 2.73.11.

EPSS 0.00013
Schedule remediation
  • SSVC automatable: yes - attacks can be scripted at scale
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-327Use of a Broken or Risky Cryptographic Algorithm
▤

Affected Packages

7
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Maven org.bouncycastle:bcpkix-debug-jdk14 MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-debug-jdk15to18 MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-debug-jdk18on MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-jdk14 MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-jdk15on MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-jdk15to18 MODERATE fixed in 1.84
Maven org.bouncycastle:bcpkix-jdk18on MODERATE fixed in 1.84
▣

Scoring & Timeline

Published to NVD15 Apr 2026 · 10:16 AM
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
yes
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
⚑

Vendor Advisories

14
rhsaRHSA-2026:11720Important
rhsaRHSA-2026:11721Important
rhsaRHSA-2026:13631Important
rhsaRHSA-2026:21772Important
suse-csafSUSE-SU-2026:1639-1
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/bcgit/bc-java/commit/656bae0dbd9b1521f840521ff786e78749fe3057
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905588
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