Security: CVE-2026-65639 CSF Security Release
CloudLinux, cPanel, CSF is affected by CVE-2026-65639. 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.
Düzeltme Komutları
EL7 (CentOS/CloudLinux 7)
sudo yum update
EL8+ (AlmaLinux/CloudLinux/Rocky)
sudo dnf update
SharedLicense lisansı altında bunun anlamı
Your SharedLicense license itself is not affected — this is a vulnerability in CloudLinux, cPanel, CSF software, not in licensing. Licenses continue to work during and after the update; there is no need to re-issue or re-activate anything. If you resell CloudLinux, cPanel, CSF under your own brand, patch client servers too — unpatched installs put your reputation at risk, not your license.
Situation
A vulnerability was found in the advanced-rule parser in the ConfigServer Security & Firewall (CSF) software which could allow a remote attacker who controls a configured allow/deny feed to execute arbitrary commands as root.
Note: By default, no remote allow/deny feed is configured.
Affected Product versions
| Product | Affected Versions | Patched Versions |
|---|---|---|
| CSF | 2.15 through 16.29 | 16.30+ |
Impact
Successful exploitation leads to code execution as the root user, giving an attacker full control of the server.
Call to action
Update to the latest version of the ConfigServer Firewall plugin:
# yum clean all
# /scripts/update-packages
# dnf clean all
# /scripts/update-packages
# apt update
# /scripts/update-packages
Mitigation
It is highly recommended that you update the installed CSF version as soon as possible.
This vulnerability is only reachable on servers configured to pull a remote allow or deny list. If updating is not possible, review those settings and remove any feed you do not fully control and trust.
- Access the server as the
rootuser via SSH, or the Terminal in WHM. -
Edit the CSF configuration file:
# nano /etc/csf/csf.conf
-
Review the
GLOBAL_DENYandGLOBAL_ALLOWoptions and clear any untrusted feed URL:CONFIG_TEXT: GLOBAL_DENY = “”
CONFIG_TEXT: GLOBAL_ALLOW = “”
-
Save and restart the CSF and LFD services:
# systemctl restart csf lfd
Note: rule data from a previously configured feed is cached on disk and re-applied when the service restarts. After updating or clearing the feed settings, review the cached list at /var/lib/csf/csf.gdeny.
Sıkça Sorulan Sorular
What is CVE-2026-65639?
Is CVE-2026-65639 being exploited in the wild?
How do I fix CVE-2026-65639?
Referanslar
Sisteminizi güvenlik açıkları açısından kontrol edin
Size uygun tam düzeltme komutlarını görmek için ürününüzü ve işletim sisteminizi seçin.
Sisteminizi Kontrol Edin