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).

CVSS

No CVSS.

References

Link	Resource
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

Configurations

No configuration.

History

03 Aug 2026, 06:16

Type	Values Removed	Values Added
References	~~{'url': 'https://github.com/bcgit/bc-java/wiki/CVE-2026-59638', 'source': '91579145-5d7b-4cc5-b925-a0262ff19630'}~~	() https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059638 -

03 Aug 2026, 01:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-03 01:16

Updated : 2026-08-04 14:50

NVD link : CVE-2026-59638

Mitre link : CVE-2026-59638

CVE.ORG link : CVE-2026-59638

JSON object : View

Products Affected

No product.

CWE

CWE-297

Improper Validation of Certificate with Host Mismatch

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