CVE-2026-42548

HIGH

Flight: Reflected XSS via unvalidated JSONP callback in Flight::jsonp()

Title source: cna
STIX 2.1

Description

Flight is an extensible micro-framework for PHP. Prior to 3.18.1, Flight::jsonp() concatenates the ?jsonp= query parameter directly into an application/javascript response body without validating that the value is a legal JavaScript identifier. An attacker can inject arbitrary JavaScript that executes in the response origin, enabling reflected cross-site scripting. This vulnerability is fixed in 3.18.1.

References (1)

Core 1
Core References

Scores

CVSS v4 8.6
EPSS 0.0034
EPSS Percentile 25.8%
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact total

Details

CWE
CWE-79
Status published
Products (2)
flightphp/core 0 - 3.18.1Packagist
flightphp/core < 3.18.1
Published May 13, 2026
Tracked Since May 14, 2026