Horizon Alert
Summary of the vulnerability and why it matters
This advisory details a critical vulnerability in RabbitMQ messaging brokers that could allow unauthorized remote access through a misconfigured trusted network path. The issue stems from how the system checks user permissions, potentially bypassing security controls under specific network conditions. While the vulnerability is severe, its exploitation depends on particular network configurations and the use of a trusted PROXY-protocol path, suggesting that directly internet-exposed instances may not be immediately at risk, but confirmation of the environment is essential.
- Authentication bypass in messaging brokers.
- Enables unauthorized remote access to systems.
- Confirm relevance and potential exposure.
Attack Path
How an attacker could exploit the issue
An attacker can bypass authentication controls in RabbitMQ by exploiting a loopback check that incorrectly uses the listener's socket address instead of the actual client's source. This allows a restricted user to connect remotely when traffic is routed through a trusted PROXY-protocol path, and the RabbitMQ backend listener is bound to loopback.
- Trusted PROXY-protocol path required.
- Loopback-bound listener is exploited.
- Allows remote access for restricted users.
Live Threat
Current exploitation, exposure, and threat context
When RabbitMQ is configured to accept traffic through a trusted PROXY-protocol path, and its backend listener is bound to the loopback interface, an attacker could potentially bypass authentication. This bypass occurs because the system incorrectly uses the listener's socket address instead of the actual client's source address for its loopback check, allowing unauthorized remote connections when supported.
- Remote authentication bypass.
- Unauthenticated access through specific configurations.
- Unauthorized system access and control.
Operational Fix
Recommended remediation, mitigation, and detection steps
Platform and infrastructure teams are likely responsible for managing RabbitMQ, with security teams overseeing network access and vendor management ensuring the product is up-to-date. The first step is to identify all RabbitMQ instances, determine their exposure and criticality, and locate the accountable owners to plan remediation based on risk.
- Platform/Infrastructure owns remediation.
- Verify RabbitMQ instance reachability and criticality.
- Plan updates or implement compensating controls.
