CVE-2025-34061: PHPStudy 2016-2018 Backdoor Remote Code Execution Vulnerability

Severity: critical (CVSS 9.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-03 · updated 2026-06-17
Weakness: CWE-94

Description

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.

Affected products

Henan Xiaopi Security Technology Co., Ltd. PHPStudy: from 2016 through 2018

References

https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/multi/http/phpstudy_backdoor_rce.rb
https://www.xp.cn/phpstudy

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