Bug 2510198 (CVE-2026-8763)

Summary: CVE-2026-8763 org.bouncycastle/bcprov-jdk15on: org.bouncycastle/bcpkix-jdk15on: Bouncy Castle for Java: Name Constraints bypass via trailing dot in rfc822Name and URI
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: amctagga, anujha, aoconnor, aschwart, asoldano, aszczucz, ataylor, bbaranow, bmaxwell, bniver, boliveir, bstansbe, dfreiber, dlofthou, drichtar, drow, ehugonne, flucifre, gmeno, groman, istudens, ivassile, iweiss, jburrell, mbenjamin, mhackett, mosmerov, mposolda, msvehla, nwallace, pberan, pesilva, pjindal, pmackay, rhel-process-autobot, rmartinc, rstancel, sostapov, ssilvert, sthorger, thjenkin, vdosoudi, vereddy, vkumar, vmuzikar, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in Bouncy Castle for Java, a cryptographic library. An attacker can exploit this vulnerability by manipulating rfc822Name and URI fields within X.509 certificates using a trailing dot. This bypasses Name Constraints, potentially leading to spoofing or unauthorized access. Such an exploit impacts the integrity and confidentiality of communications.
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2519406, 2519473, 2519474    
Bug Blocks:    

Description OSIDB Bzimport 2026-08-03 02:01:46 UTC
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).