CVE-2026-40560

HIGH

Starman versions before 0.4018 for Perl allows HTTP Request Smuggling via Improper Header Precedence

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 7.5
EPSS 0.0003
EPSS Percentile 8.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-444
Status published
Products (1)
MIYAGAWA/Starman < 0.4018
Published Apr 29, 2026
Tracked Since Apr 29, 2026