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).
Scoring
- Severity
- CRITICAL
- CVSS base score
- 9.3
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/U:Amber
- EPSS probability
- 0.21%
- CWE
- CWE-297
- Published
- 2026-08-03
- Last modified
- 2026-08-03
Affected products
- Legion of the Bouncy Castle Inc. BC-JAVA
- Legion of the Bouncy Castle Inc. BC-LTS-JAVA
- Legion of the Bouncy Castle Inc. BC-FJA
- Legion of the Bouncy Castle Inc. BC-FJA
- Legion of the Bouncy Castle Inc. BC-FJA
Weakness type
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