The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has given U.S. government agencies three days to secure their servers against an actively exploited vulnerability (CVE-2026-54420) in the LiteSpeed cPanel user-end plugin. Tracked as CVE-2026-48172, this high-severity vulnerability was reported by Namecheap and allows attackers with FTP or web shell access to escalate privileges to root on shared hosting servers running CloudLinux/CageFS. This vulnerability affects all user-end plugin versions before 2.4.8 and stems from a 'UNIX symlink following' weakness. LiteSpeed flagged it as actively exploited in early June and released urgent security updates, warning users to update the cPanel user-end plugin (bundled with the WHM plugin) to the latest version. Users are advised to use the following command to check if their server is vulnerable to attacks targeting the CVE-2026-48172 vulnerability: "If this command results in any output, the vulnerability may have been exploited on your server. [..] To determine any damage done, examine the system logs for any actions taken by the detected IPs," LiteSpeed said. "This vulnerability is being actively exploited, and poses a risk for all user-end plugin versions prior to 2.4.8." On Monday, CISA also added that the vulnerability to its Known Exploited Vulnerabilities Catalog (KEV), ordering Federal Civilian Executive Branch (FCEB) agencies to secure their systems within three days, as required by Binding Operational Directi...
CISA warns of another cPanel plugin flaw exploited in attacks
BleepingComputer
·Sergiu Gatlan
·Published Jun 16, 2026
·Updated
Affected Software
1 affected component
LiteSpeed cPanel user-end plugin<2.4.8
Frequently Asked Questions
1
What is the main topic of this article?
The article discusses a high-severity vulnerability in the LiteSpeed cPanel user-end plugin that is actively being exploited.
2
What security implications are discussed?
CISA warns that U.S. government agencies must secure their servers against the vulnerability to prevent exploitation.
3
What specific vulnerability is referenced in the article?
The vulnerability is tracked as CVE-2026-54420 in the LiteSpeed cPanel user-end plugin.
4
How much time do government agencies have to address the vulnerability?
Government agencies have three days to secure their servers against the vulnerability.
5
When was this security warning published?
The warning was published on June 16, 2026.