CVE-2026-59638
In Bouncy Castle for Java before 1.85, JSSE hostname verifier CN-fallback enabled by default despite documented opt-in. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).
- Score
- CVSS 4.0 9.3 Critical
- Status
- Analyzed - 91579145-5d7b-4cc5-b925-a0262ff19630
- Published
- 2026-08-03
- Last modified
- 2026-08-03
- Weaknesses
- CWE-297
Affected products
- Bc-java (Bouncycastle)
- Bctls-fips (Bouncycastle)
- Bouncy Castle For Java Lts (Bouncycastle)
- Bc-fja (Legion Of The Bouncy Castle Inc.)
- Bc-java (Legion Of The Bouncy Castle Inc.)
- Bc-lts-java (Legion Of The Bouncy Castle Inc.)
References
- https://github.com/bcgit/bc-java/commit/5ac55351cd1a8a7184d41c96a7ee87df0770240a
- https://github.com/bcgit/bc-java/commit/799bd15320a6310a447863638aa3df64acef829b
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059638
