A flaw was found in pki-core. The certificate authority (CA) renewal request path does not perform the realm-based authorization check that the enrollment path performs, allowing an authenticated user entitled to one realm to cause a certificate belonging to a different realm to be renewed without that realm's authorization.
Deployments that do not configure a realm-mapped authorization manager (AuthzRealmDefault with a non-default realm-to-authorization-manager mapping) for multi-tenant or delegated sub-CA use are not exposed to this issue. For deployments that do use realm-based authorization, using a renewal profile that additionally restricts renewal requests to the original requester narrows exposure: the shipped caDirUserRenewal.cfg profile configures authz.acl=user_origreq="auth_token.uid", which independently blocks cross-user renewal by comparing the renewing caller's UID against the UID that submitted the original request. This is a partial mitigation only -- it is realm-blind rather than realm-aware, so a UID collision across two independently-administered realms' user directories would still bypass it -- and it does not apply to caManualRenewal.cfg or other shipped renewal profiles that configure no authz.acl, which remain exploitable as described. No complete mitigation is available; apply the update once released.