Zero-Day Advisory

Fortinet Discovers LiveZilla Server Denial Of Service Vulnerability


Fortinet's FortiGuard Labs has discovered a Denial of Service Vulnerability in LiveZilla Server.

LiveZilla, the Next Generation Live Help and Live Support System connects you to your website visitors.

LiveZilla Server is susceptible to a Denial of Service vulnerability. The issue occurs when the server try to concat dot-dot-slash based on user input times, result to crash server.


FortiGuard Labs released the following FortiGate IPS signature which covers this specific vulnerability:

Released Jun 26, 2019

Users should apply the solution provided by LiveZilla


Fortinet reported the vulnerability to LiveZilla on 22 June, 2019. 

LiveZilla confirmed the vulnerability on 24 June, 2019. 

LiveZilla released patch for the vulnerability on 26 June, 2019.


This vulnerability was discovered by Nguyen Thanh Nguyen of Fortinet's FortiGuard Labs.

IPS Subscription

Fortinet customers who subscribe to Fortinet's intrusion prevention (IPS) service should be protected against this vulnerability with the appropriate configuration parameters in place. Fortinet's IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by FortiGuard Labs, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.