CVE-2026-18141 Red Hat CVE debrief

Who should care

Organizations using Ansible Automation Platform's Event-Driven Ansible (EDA) should be aware of this vulnerability and take steps to verify their configurations and protect against potential attacks. This includes reviewing EDA workflows, ensuring mTLS authentication is properly enforced, and implementing compensating controls to detect potential unauthorized event injections. Security teams and operators responsible for EDA deployments should prioritize verification and remediation efforts to prevent potential security breaches.

Technical summary

A flaw in aap-gateway, a component of Ansible Automation Platform's Event-Driven Ansible (EDA), allows an unauthenticated remote attacker to bypass mutual Transport Layer Security (mTLS) authentication for event streams by manipulating the event stream URL and forging the HTTP Subject header. This vulnerability enables attackers to inject arbitrary events into EDA, potentially triggering automated workflows. The system inadvertently discloses the expected certificate subject in error messages, simplifying the attack. To mitigate, verify EDA configurations to ensure mTLS authentication is properly enforced and implement compensating controls to detect potential unauthorized event injections.

Defensive priority

Organizations using Ansible Automation Platform's Event-Driven Ansible (EDA) should prioritize verification of their configurations and implement compensating controls to detect potential unauthorized event injections.

Recommended defensive actions

• Verify EDA configurations to ensure mTLS authentication is properly enforced.
• Implement compensating controls to detect potential unauthorized event injections.
• Monitor event streams for suspicious activity.
• Review and update EDA workflows to prevent automated triggering based on injected events.
• Conduct inventory checks to identify affected systems and apply vendor remediation.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability in aap-gateway, a component of Ansible Automation Platform's Event-Driven Ansible (EDA). The vulnerability allows an unauthenticated remote attacker to bypass mutual Transport Layer Security (mTLS) authentication for event streams. Evidence is limited to public sources and may not reflect the full scope or impact of the vulnerability. Defenders should verify configurations, review event streams, and monitor for suspicious activity.

Official resources