Ansible Automation Platform EUVD-2026-44739

Exploitation requires that the AAP Gateway expose the non-mTLS route to EDA event streams - the specific misconfigured path where Envoy fails to remove the inbound Subject header; deployments that only serve EDA event streams over enforced mTLS are not exposed via this vector. The attacker must also supply a Subject header whose value matches the Distinguished Name (DN) of a legitimate client certificate, so knowledge of a valid client DN is a concrete prerequisite that limits blind exploitation. Beyond those two conditions, the CVSS vector (AV:N/AC:L/PR:N/UI:N) indicates no authentication, no user interaction, and network reachability of the Gateway are the only remaining requirements.

The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N, 8.2 High) indicates network-reachable, low-complexity, unauthenticated exploitation with high integrity impact and no availability impact - consistent with the description of arbitrary event injection. There is a meaningful real-world limiting factor the raw score understates: the attacker must know a legitimate client certificate's Distinguished Name to forge a matching Subject header, so exploitation is not purely blind and favors an attacker with some environmental knowledge. No EPSS probability, KEV listing, POC, or SSVC decision data was provided, so automatability and in-the-wild exploitation status are unknown. The confidentiality metric is worth scrutiny: the described impact is event injection (integrity), not data disclosure, so the vendor's C:L is arguable and I assess confidentiality impact as marginal. Net: a credible high-severity integrity risk in Red Hat environments running the affected EDA configuration, but priority should be weighted by whether the non-mTLS EDA route is actually in use and how discoverable valid certificate DNs are.

An unauthenticated attacker who can reach the AAP Gateway over the network and who has learned a valid client certificate's Distinguished Name sends an ordinary HTTP request to the non-mTLS EDA event-stream route with a forged Subject header set to that DN. Because Envoy does not strip the header on this route, the request is treated as an authenticated client, and the attacker injects arbitrary events into a protected EDA stream - potentially triggering unauthorized automation. No public POC was identified, but the low attack complexity (AC:L) and lack of required privileges (PR:N) make the technique straightforward once a legitimate DN is known.