A flaw was found in Rancher Manager. The SAML assertion replay protection introduced by the fix for CVE-2026-44946 recorded consumed assertion IDs in a per-process cache, so each replica only detected replays that reached the same pod. In a high-availability deployment, an attacker holding a captured assertion could replay it once against every other replica to obtain additional authenticated sessions as the victim.
This issue affects Rancher: before 2.15.1.