A vulnerability in MIYAGAWA Starman allows unauthenticated attackers to perform HTTP request smuggling, potentially leading to unauthorized data access.

The application incorrectly prioritizes the Content-Length header over the Transfer-Encoding header when both are present, violating RFC 7230 standards. This flaw allows an unauthenticated attacker to smuggle malicious HTTP requests through a front-end reverse proxy.

Successful exploitation of this vulnerability allows an attacker to bypass security controls implemented by front-end proxies, potentially leading to unauthorized access to downstream applications or sensitive data. With a CVSS score of 7.5, this high-severity flaw poses a significant risk to system integrity and confidentiality, as it facilitates the injection of arbitrary requests into the application stream.

Immediate Action: Upgrade the Starman module to version 0.4018 or later to incorporate the proper header precedence logic.

Proactive Monitoring: Monitor server access logs for anomalous HTTP request patterns or suspicious header combinations that deviate from standard traffic profiles.

Compensating Controls: Deploy a Web Application Firewall (WAF) configured to inspect and normalize HTTP headers, ensuring that conflicting Content-Length and Transfer-Encoding headers are rejected or sanitized before reaching the backend.

Public Exploit Available: Unknown

Given the critical nature of request smuggling vulnerabilities, IT administrators should prioritize the update of the Starman module to version 0.4018. Failure to patch leaves the application susceptible to request manipulation attacks that can bypass perimeter security. Immediate application of the provided vendor fix is required to fully mitigate this risk.