Bug 2521775 (CVE-2026-78323)

Summary: CVE-2026-78323 jss: jss: JSSTrustManager does not verify NSS trust flags on CA certificates
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: aakkiang, cfu, edewata, gkimetto, jmagne, mfargett, prisingh, rhel-process-autobot, skhandel, snegrini, taherrin, 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 JSS (Java Security Services). The JSSTrustManager class does not verify NSS trust flags when validating CA certificates, allowing certificates present in the NSS database without TRUSTED_CA flags to be accepted as trust anchors for TLS connections. In non-default configurations where certificate revocation checking is disabled, this could allow a man-in-the-middle attacker to forge certificates accepted by PKI client connections.
 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: 2521776    
Bug Blocks:    

Description OSIDB Bzimport 2026-08-24 09:39:15 UTC 
A flaw was found in JSS (Java Security Services). The JSSTrustManager class, which implements javax.net.ssl.X509TrustManager for JSS-based TLS connections, does not filter CA certificates by NSS trust flags when building its set of accepted issuers. The getAcceptedIssuers() method returns all certificates with basicConstraints CA=TRUE from the NSS database regardless of whether they carry TRUSTED_CA trust flags, and checkSignature() performs only cryptographic signature validation against this unfiltered set. This means a certificate present in the NSS database with only VALID_CA flags (as set by routine operations such as certificate enrollment via CERT_ImportCAChainTrusted) could be treated as a trust anchor for TLS connections. In default configurations, the native revocation verification check (certChainRevokeVerify) catches this condition because NSS's native verification properly validates trust flags. However, if revocation checking is disabled, an attacker controlling the private key of an under-trusted CA could forge certificates accepted by JSSTrustManager, enabling man-in-the-middle attacks on outbound PKI client connections.