CVE-2026-8763

In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bcgit/bc-java/commit/2c28b253a44681fbbc562561eab6ad383d2ae558	Patch
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908763	Third Party Advisory Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:bouncycastle:bc-java::::::::
	cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts::::::::
	cpe:2.3:a:bouncycastle:fips_java_api::::::::
	cpe:2.3:a:bouncycastle:fips_java_api::::::::
	cpe:2.3:a:bouncycastle:fips_java_api::::::::

History

No history.

Information

Published : 2026-08-03 01:16

Updated : 2026-09-02 14:28

NVD link : CVE-2026-8763

Mitre link : CVE-2026-8763

CVE.ORG link : CVE-2026-8763

JSON object : View

Products Affected

bouncycastle

bouncy_castle_for_java_lts
bc-java
fips_java_api

CWE

CWE-295

Improper Certificate Validation

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This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series)."}], "lastModified": "2026-09-02T14:28:48.940", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6A5663-2E62-44AA-8A64-A3CB0DC8813B", "versionEndExcluding": "1.85"}, {"criteria": "cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F5ED4F42-08FF-4642-815D-1ED0C82FDBD2", "versionEndIncluding": "2.73.11"}, {"criteria": "cpe:2.3:a:bouncycastle:fips_java_api:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BDB0974E-66FC-45AB-9F1B-0E80B86A4D06", "versionEndExcluding": "1.0.2.7", "versionStartIncluding": "1.0.0"}, {"criteria": "cpe:2.3:a:bouncycastle:fips_java_api:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B1C285AC-E2BF-4A23-BCD4-494CB5B2C42D", "versionEndExcluding": "2.0.2", "versionStartIncluding": "2.0.0"}, {"criteria": "cpe:2.3:a:bouncycastle:fips_java_api:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BF53C833-06C3-4BDC-BEF6-50A8B8A0A47C", "versionEndExcluding": "2.1.3", "versionStartIncluding": "2.1.0"}], "operator": "OR"}]}], "sourceIdentifier": "91579145-5d7b-4cc5-b925-a0262ff19630"}