Critical severity · published Sep 10, 2026
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…
9.2
CVSS
2.3%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)2.3% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CS
ConfigServer Security & Firewall · WebPros
14.00 before 16.30 · source: vendor
Affected product
CS
ConfigServer Security & Firewall
ConfigServer
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–
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