Bug 2463704 (CVE-2026-40560)

Summary: CVE-2026-40560 Starman: Starman: HTTP Request Smuggling via improper header precedence
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: high    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in Starman. Starman versions before 0.4018 for Perl incorrectly prioritize the "Content-Length" header over "Transfer-Encoding: chunked" when both are present in an HTTP request, violating RFC 7230 3.3.3. A remote attacker could exploit this improper header precedence to perform HTTP Request Smuggling, allowing them to send malicious HTTP requests through a front-end reverse proxy. This could lead to unauthorized access or manipulation of web traffic.
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Bug Depends On: 2463795    
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Description OSIDB Bzimport 2026-04-29 00:01:28 UTC 
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.