CVE-2026-8763 Details
Description
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).
A vulnerability exists in Bouncy Castle for Java in versions prior to 1.85, as well as in Bouncy Castle for Java LTS prior to 2.73.12 and Bouncy Castle for Java FIPS (BC-FJA) versions 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series). This vulnerability allows a compromised or mis-issuing name-constrained intermediate CA to bypass name constraints by exploiting trailing dots in rfc822Name and URI fields. The issue arises because the validation process for these fields does not properly account for trailing dots, which can be used to evade constraints.
Users can upgrade to Bouncy Castle for Java version 1.85 or later, Bouncy Castle for Java LTS version 2.73.12 or later, or Bouncy Castle for Java FIPS version 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) or 2.1.3 (2.1.X series).
Metrics
CVSS 4.0 Severity and Vector Strings:
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Aug 3, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/bcgit/bc-java/commit/2c28b253a44681fbbc562561eab6ad383d2ae558 | bcorg | Patch |
| https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908763 | bcorg | Third Party AdvisoryPatch |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-295 | Improper Certificate Validation | bcorg |
Affected Products
| Product | Versions |
|---|---|
| bouncycastle bc-java | < 1.85 |
CPE
Remediation
| |
| bouncycastle bouncy castle for java lts | <= 2.73.11 |
CPE
Remediation
| |
| bouncycastle fips java api | >= 1.0.0, < 1.0.2.7 >= 2.0.0, < 2.0.2 >= 2.1.0, < 2.1.3 |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 2, 2026 | Initial Analysis | [email protected] |
| Aug 3, 2026 | CVE Modified | CISA-ADP |
| Aug 3, 2026 | CVE Modified | bcorg |
| Aug 3, 2026 | New CVE Received | bcorg |