Vulnerability Description
Starman versions before 0.4018 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Starman 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 |
|---|---|---|
| Miyagawa | Starman | < 0.4018 |
Related Weaknesses (CWE)
References
- https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3Third Party Advisory
- https://github.com/miyagawa/Starman/commit/ced205f0805027e9d9c0731f8c40b10422060PatchThird Party Advisory
- https://metacpan.org/release/MIYAGAWA/Starman-0.4018/changesProductRelease Notes
- http://www.openwall.com/lists/oss-security/2026/04/29/1Mailing ListThird Party Advisory
FAQ
What is CVE-2026-40560?
CVE-2026-40560 is a vulnerability with a CVSS score of 7.5 (HIGH). Starman versions before 0.4018 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Starman incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both head...
How severe is CVE-2026-40560?
CVE-2026-40560 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-2026-40560?
Check the references section above for vendor advisories and patch information. Affected products include: Miyagawa Starman.