CVE-2026-40562
Last modified
CVE-2026-40562 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 0.32% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Kazeburo | Gazelle | < 0.50 |
References
- https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/05/06/7Mailing List, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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