CVE-2026-42551

HIGH

Flight: HTTP method override enabled by default enables CSRF escalation and middleware bypass in flightphp/core

Title source: cna
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0031
EPSS Percentile 22.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-436
Status published
Products (2)
flightphp/core 0 - 3.18.1Packagist
flightphp/core < 3.18.1
Published May 13, 2026
Tracked Since May 14, 2026