CVE-2026-40560

HIGH EPSS 38.3%
Published Apr 29, 20262mo ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
High
Find Similar
Published Apr 29, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

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 Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability None

Threat Intelligence

EPSS Exploit Probability
38.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-444

Affected Products 1

VendorProductVersionRange
miyagawastarman* <0.4018

References 4

  • openwall.com http://www.openwall.com/lists/oss-security/2026/04/29/1
    Mailing ListThird Party Advisory
  • datatracker.ietf.org https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3
    Third Party Advisory
  • github.com https://github.com/miyagawa/Starman/commit/ced205f0805027e9d9c0731f8c40b104220604ed.patch
    PatchThird Party Advisory
  • metacpan.org https://metacpan.org/release/MIYAGAWA/Starman-0.4018/changes
    ProductRelease Notes

Remediation

  • github.com https://github.com/miyagawa/Starman/commit/ced205f0805027e9d9c0731f8c40b104220604ed.patch
    PatchThird Party Advisory