RCE in Configserver Security & Firewall

CVE-2026-65638

Improper escaping of a request URL in ConfigServer Security & Firewall allows an unauthenticated remote attacker to execute arbitrary commands as the CSF service account via shell command injection. The vulnerability affects versions of the software originally distributed by ConfigServer, as well as versions of the WebPros-maintained fork that contain the vulnerable code. WebPros has addressed the vulnerability in version 16.30. Other forks or independently maintained versions of ConfigServer Security & Firewall (CSF) may also be affected and should be evaluated independently.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

EPSS exploit prediction

EPSS: 0.023 (83.4th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 83rd percentile — 83.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-65638: held from 0.023 to 0.023.

EPSS over last 30 days · oldest: 0.023 · newest: 0.023 · change: 0.000

Affected products

Weakness classification (CWE)

References