Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Kazeburo | Gazelle | < 0.50 |
Related Weaknesses (CWE)
References
- https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3Third Party Advisory
- https://metacpan.org/release/KAZEBURO/Gazelle-0.50/changesRelease Notes
- https://security.metacpan.org/patches/G/Gazelle/0.49/CVE-2026-40562-r1.patchPatch
- http://www.openwall.com/lists/oss-security/2026/05/06/7Mailing ListThird Party Advisory
FAQ
What is CVE-2026-40562?
CVE-2026-40562 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 heade...
How severe is CVE-2026-40562?
CVE-2026-40562 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-40562?
Check the references section above for vendor advisories and patch information. Affected products include: Kazeburo Gazelle.