CVE-2026-40560

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3	Third Party Advisory
https://github.com/miyagawa/Starman/commit/ced205f0805027e9d9c0731f8c40b104220604ed.patch	Patch Third Party Advisory
https://metacpan.org/release/MIYAGAWA/Starman-0.4018/changes	Product Release Notes
http://www.openwall.com/lists/oss-security/2026/04/29/1	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:miyagawa:starman:*:*:*:*:*:perl:*:*

History

No history.

Information

Published : 2026-04-29 00:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-40560

Mitre link : CVE-2026-40560

CVE.ORG link : CVE-2026-40560

JSON object : View

Products Affected

miyagawa

starman

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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