Cross-site scripting in Hestia Control Panel - #VU165959
Published: November 12, 2026
Vulnerability identifier: #VU165959
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: N/A
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary JavaScript in a victim's browser within the Hestia Control Panel origin and perform actions with the victim's privileges.
The vulnerability exists due to missing HTML escaping of request and session array keys in web/templates/pages/debug_panel.php when rendering the panel with debug mode enabled. A remote attacker can trick a logged-in user into visiting a panel URL containing a query key such as <img/src=x/onerror=alert(1)> to execute JavaScript through reflected cross-site scripting.
Affected software
Hestia Control Panel
Remediation
Install security update from vendor's website.
Hestia Control Panel - update to 1.10.6