CVE-2026-40562

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

Published May 6, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
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.

Remediation

Vendor Solution

Upgrade to Gazelle 0.50 or later.


Vendor Workaround

Migrate to Starman version 0.4018 or newer which has fixed the issue. Or apply the patch.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:2.3:a:kazeburo:gazelle:*:*:*:*:*:perl:*:*
Type Values Removed Values Added
First Time appeared Kazeburo
Kazeburo gazelle
Vendors & Products Kazeburo
Kazeburo gazelle
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Gazelle versions through 0.49 for Perl allows HTTP Request Smuggling via Improper Header Precedence
Weaknesses CWE-444
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
CPANSec
Published
Updated
May 7, 2026, 4:13 PM
Reserved
Apr 14, 2026, 11:35 AM
Status
Analyzed
Published
May 6, 2026, 1:16 PM
Modified
Oct 26, 2026, 7:10 PM