CVE-2025-34061
CRITICAL 9.3EPSS 1.7%
A backdoor in PHPStudy versions 2016 through 2018 allows unauthenticated remote attackers to execute arbitrary PHP code on affected installations. The backdoor listens for base64-encoded PHP payloads in the Accept-Charset HTTP header of incoming requests, decodes and executes the payload without proper validation. This leads to remote code execution as the web server user, compromising the affected system.
- CVSS v4.0
- 9.3 CRITICAL
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/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 - EPSS
- 1.68% chance of exploitation in the next 30 days, 75th percentile
- Published
- 2025-07-03
- Updated
- 2025-07-07