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.
Problem types
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Product status
Any version
Timeline
| 2026-04-12: | Issue identified by CPANSec |
| 2026-04-29: | Issue reported to software maintainer |
| 2026-05-06: | Issue disclosed by CPANSec |
| 2026-05-07: | Gazelle 0.50 released |
Credits
CPANSec
References
www.openwall.com/lists/oss-security/2026/05/06/7
datatracker.ietf.org/doc/html/rfc7230
security.metacpan.org/...azelle/0.49/CVE-2026-40562-r1.patch
metacpan.org/release/KAZEBURO/Gazelle-0.50/changes