CVE-2026-40562

high

Description

Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Gazelle 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.

References

https://security.metacpan.org/patches/G/Gazelle/0.49/CVE-2026-40562-r1.patch

https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3

http://www.openwall.com/lists/oss-security/2026/05/06/7

Details

Source: Mitre, NVD

Published: 2026-05-06

Updated: 2026-05-06

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:C/A:N

Severity: High

CVSS v3

Base Score: 7.5

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

Severity: High