Legion of the Bouncy Castle Java Cryptography API Bleichenbacher Oracle VulnerabilityGHSA-m26p-m559-g5j5
GHSA-m26p-m559-g5j5 is a security vulnerability in bouncycastle:bcprov-jdk14. A fix is available for bouncycastle:bcprov-jdk14 — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
bouncycastle:bcprov-jdk14☕bouncycastle:bcprov-jdk15☕bouncycastle:bcprov-jdk16Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
The Legion of the Bouncy Castle Java Cryptography API before release 1.38, as used in Crypto Provider Package before 1.36, has unknown impact and remote attack vectors related to "a Bleichenbacher vulnerability in simple RSA CMS signatures without signed attributes."
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | bouncycastle:bcprov-jdk14 | all versions | 1.38bouncycastle:bcprov-jdk14:1.38 |
| ☕Maven | bouncycastle:bcprov-jdk15 | all versions | 1.38bouncycastle:bcprov-jdk15:1.38 |
| ☕Maven | bouncycastle:bcprov-jdk16 | all versions | 1.38bouncycastle:bcprov-jdk16:1.38 |
Affected Products
bc-javabouncycastlebouncy-castle-crypto-packagebouncycastleDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for bouncycastle:bcprov-jdk14, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update bouncycastle:bcprov-jdk14 to 1.38 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m26p-m559-g5j5 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is GHSA-m26p-m559-g5j5 in your dependencies?
Find it across Maven, including transitive dependencies.