CVE-2025-34061
Critical
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.
SeverityCritical
CVSS9.3
Exploit probability—
ProductPHPStudy
PublishedJul 3, 2025
First seenJul 3, 2025
Weakness typeCWE-94Code injection
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Henan Xiaopi Security Technology Co., Ltd. PHPStudy | 2016 ≤ v ≤ 2018 | — |
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