CVE-2026-42551 — HIGH (7.5)

Vulnerability Description

Flight is an extensible micro-framework for PHP. Prior to 3.18.1, Request::getMethod() unconditionally honors the X-HTTP-Method-Override header and the $_REQUEST['_method'] parameter on any HTTP verb (including safe verbs such as GET), with no opt-in and no whitelist of permitted target methods. A GET request can silently become a DELETE or PUT, enabling CSRF escalation against destructive endpoints, bypass of middleware gated on unsafe verbs, and cache poisoning between CDN and origin. This vulnerability is fixed in 3.18.1.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

HIGH

Availability

NONE

Related Weaknesses (CWE)

CWE-436

References

FAQ

What is CVE-2026-42551?

CVE-2026-42551 is a vulnerability with a CVSS score of 7.5 (HIGH). Flight is an extensible micro-framework for PHP. Prior to 3.18.1, Request::getMethod() unconditionally honors the X-HTTP-Method-Override header and the $_REQUEST['_method'] parameter on any HTTP verb ...

How severe is CVE-2026-42551?

CVE-2026-42551 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-2026-42551?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.