CVE-2026-40560

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

29/04/2026

Last modified:

06/05/2026

Description

Starman versions before 0.4018 for Perl allows HTTP Request Smuggling via Improper Header Precedence.<br /> <br /> 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.<br /> <br /> An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): None
Availability (A): None