A Vulnerability in Fortinet FortiWeb Could Allow for Arbitrary Code Execution

ITS Advisory Number: 
2021-150
Date(s) Issued: 
Monday, November 22, 2021
Subject: 
A Vulnerability in Fortinet FortiWeb Could Allow for Arbitrary Code Execution
Overview: 

A vulnerability has been discovered in Fortinet FortiWeb that could allow for arbitrary code execution. Fortinet FortiWeb is a firewall for web applications, which provides threat protection for medium and large enterprises. Successful exploitation of this vulnerability could allow for arbitrary code execution within the context of the affected application. Depending on the privileges associated with this application, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. If this application has been configured to have fewer user rights on the system, exploitation of this vulnerability could have less impact than if it was configured with administrative rights.

 

THREAT INTELLIGENCE:

There are currently no reports of this vulnerability being exploited in the wild.

 

Systems Affected: 
  • FortiWeb versions prior to 6.4.1
  • FortiWeb versions prior to 6.3.16
  • FortiWeb versions prior 6.2.6
RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
Medium
BUSINESS
Large and medium business entities: 
High
Small business entities: 
Medium
Home Users: 
Low
Description: 

A vulnerability has been discovered in Fortinet FortiWeb, that could allow for arbitrary code execution. This vulnerability can be exploited when an unauthenticated attacker overwrites the content of the stack by sending crafted HTTP requests with large request parameter values.

 

Successful exploitation of this vulnerability could allow for arbitrary code execution within the context of the affected application. Depending on the privileges associated with this application, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. If this application has been configured to have fewer user rights on the system, exploitation of this vulnerability could have less impact than if it was configured with administrative rights.

Actions: 
  • After appropriate testing, immediately apply updates by Fortinet to vulnerable systems.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Inform and educate users regarding threats posed by hypertext links contained in emails or attachments, especially from un-trusted sources.