CVE Catalog

CVE-2026-40560

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.49%

39th percentile - higher than 39% of all known CVEs

Summary

Starman for Perl before version 0.4018 is vulnerable to HTTP Request Smuggling due to improper header precedence. Starman incorrectly prioritizes Content-Length over Transfer-Encoding: chunked, violating RFC 7230. An attacker can exploit this to smuggle malicious HTTP requests through a front-end reverse proxy.

Risk Assessment

The risk involves bypassing reverse proxy security controls and executing unauthorized actions on the server, potentially leading to data integrity breaches or privilege escalation.

Recommendation

Immediately upgrade Starman to version 0.4018 or later, which correctly follows the Transfer-Encoding header precedence as per RFC.

Related vulnerabilities

Original NVD description (English source)

Starman versions before 0.4018 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Starman incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence. An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS