CVE-2026-65639

Status: Awaiting AnalysisCritical (9.5)—

OS command injection in the advanced-rule parser of ConfigServer Security & Firewall allows a remote attacker who controls a configured allow/deny feed to execute arbitrary commands as root, due to insufficient validation of feed-supplied rule data.

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.

CVSS

Version: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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
Base score: 9.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.42%
Percentile among all scored CVEs: 72
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1059 Command and Scripting Interpreterexecution90 %
Secondary impactT1068 Exploitation for Privilege Escalationprivilege escalation80 %

Vector CVSS AV:N/PR:N indica acceso remoto sin privilegios previos (T1190). CWE-78 (command injection) y ejecución como root sustentan T1059 e T1068.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Configserver — Security & Firewall^AI

CWEs

CWE-78

References

https://support.cpanel.net/hc/en-us/articles/43387923160343-Security-CVE-2026-65639-CSF-Security-Release

Raw JSON (NVD)

Show

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  "lastModified": "2026-09-10T19:54:25.810",
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