CVE-2026-56098: Observable Discrepancy

Vulnerability summary

CVE-2026-56098 is a medium (CVSS 4.3) Observable Discrepancy vulnerability. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22% of scored vulnerabilities.

Timeline

1. 01-10-2026
   PublishedVulnerability first disclosed.
2. 07-10-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in rubygem-katello. The RegistryProxiesController in Katello contains an authorization bypass vulnerability due to an execution fall-through in the registry_authorize filter. While the application identifies unauthorized requests and triggers an error response via the unauthorized method, it fails to halt the execution of the current code path (missing return statement). This failure in the control flow allows the application to proceed into subsequent business logic and database validation filters. Consequently, the application reveals its internal state through differential responses, allowing an unprivileged attacker to enumerate valid Users, Organizations, and Products across the entire instance.

• CWE-203Observable DiscrepancyThe product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.