CVE-2026-40562

Summary

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.

Affected Software

Weaknesses

• CWE-444: CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Workarounds

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

ADP Enrichment

CISA ADP Vulnrichment

• SSVC:
• Exploitation: none
  • Automatable: yes
  • Technical Impact: partial

CVE Program Container

Additional References

• http://www.openwall.com/lists/oss-security/2026/05/06/7

References

• https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3
• https://security.metacpan.org/patches/G/Gazelle/0.49/CVE-2026-40562-r1.patch
• https://metacpan.org/release/KAZEBURO/Gazelle-0.50/changes

• ←Previous
• Next→