CVE-2026-40561
5.3 · MEDIUMOverview
CVE-2026-40561 is a medium-severity vulnerability affecting kazuho starlet. It was published on May 3, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence.
Starlet 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.
Remediation
Check the references section for vendor advisories and patches from kazuho. Update starlet to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| kazuho | starlet | 0 | Affected |
Frequently Asked Questions
What is CVE-2026-40561?
CVE-2026-40561 is a medium-severity vulnerability affecting kazuho starlet. It was published on May 3, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-40561?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-40561?
Check the references section for vendor advisories and patches from kazuho. Update starlet to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40561?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40561 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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