REDHAT-BUG-2506720: Low severity Red Hat pki-core vulnerability

A flaw was found in pki-core. In the Dogtag/pki-core Certificate Authority (CA) profile framework, the certificate enrollment path (EnrollmentProcessor) calls AuthzSubsystem.checkRealm() to verify that the calling principal is authorized to act within the request's configured realm before the request is submitted. The certificate renewal path (RenewalProcessor), which is reachable from the same public REST endpoint (caProfileSubmit, and the legacy v1/CertRequestDAO and ProfileSubmitServlet entry points) and is selected purely by a client-controlled 'isRenewal' flag in the posted request body, runs the same populate-then-submit sequence and stamps the same realm onto the request via the shared AuthzRealmDefault policy default, but never calls checkRealm. As a result, a caller who is only entitled in realm A can submit a renewal naming the serial number of a certificate originally issued under realm B; the renewal request is repopulated with realm B and submitted to realm B's request queue without realm B's authorization manager ever being consulted. This was dynamically reproduced end-to-end in an isolated sandbox: an identity with zero entitlement to a configured realm, freshly confirmed denied on the equivalent enrollment call, successfully renewed another user's certificate in that realm via a single authenticated request, with checkRealm never invoked. Direct testing established the practical impact is narrower than a realm-authorization bypass might suggest: the resulting certificate's content is already retrievable by any unauthenticated caller via the product's own intended read API, confirmed both same-host and across a genuine cross-container network boundary (no net-new confidentiality exposure); no private key material is ever exposed (no impersonation path); and the victim's own certificate and their own ability to renew it are both completely unaffected (no denial-of-service capability via revocation, side-effects, or resource exhaustion -- all tested directly). Attack Complexity is assessed High because exploitability additionally requires a non-default, supported deployment configuration (a realm-mapped authorization manager, the multi-realm/delegated-CA deployment mode), per Red Hat's documented CVSS scoring practice for configuration-dependent flaws. This affects the Dogtag PKI CA codebase across all current Red Hat package names for it: pki-core (RHEL 6-9, Certificate System 9), dogtag-pki (RHEL 10, RHIVOS 2, Fedora), and redhat-pki (Certificate System 10/11) -- the same missing checkRealm call was independently confirmed present in EnrollmentProcessor and absent from RenewalProcessor at the exact upstream versions shipped as dogtag-pki 11.9.0 and redhat-pki 11.10.0, not merely inferred from shared upstream provenance. Git history analysis shows the gap was introduced by omission in commit e2de26769761af04b9c56071bd1a1926903c49b6 (2016-05-09), which added the realm check only to EnrollmentProcessor roughly 63 hours after a separate commit had modified both EnrollmentProcessor and RenewalProcessor symmetrically at the same code location -- indicating an oversight rather than an intentional design decision.