CVE-2019-17656 Explained : Impact and Mitigation

Fortinet FortiProxy and FortiOS are affected by a Stack-based Buffer Overflow vulnerability that could be exploited by an authenticated remote attacker to crash the service.

Understanding CVE-2019-17656

This CVE involves a security vulnerability in the HTTPD daemon of FortiOS and FortiProxy versions, potentially leading to service disruption.

What is CVE-2019-17656?

The vulnerability in FortiOS and FortiProxy versions allows an attacker to crash the service by sending a specially crafted PUT request.

The Impact of CVE-2019-17656

The vulnerability has a CVSS base score of 5.4 (Medium severity) and could be exploited by an authenticated remote attacker to cause service disruption.

Technical Details of CVE-2019-17656

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The HTTPD daemon in FortiOS and FortiProxy versions is susceptible to a Stack-based Buffer Overflow vulnerability.

Affected Systems and Versions

Fortinet FortiProxy versions 1.0.x, 1.1.x, 1.2.9 and below, 2.0.0 and below
FortiOS versions 6.0.10 and below, 6.2.2 and below

Exploitation Mechanism

To exploit this vulnerability, an authenticated remote attacker needs to send a specifically crafted PUT request to the server.

Mitigation and Prevention

Protect your systems from CVE-2019-17656 with the following steps:

Immediate Steps to Take

Apply vendor-supplied patches promptly
Monitor network traffic for any suspicious activity
Restrict network access to the affected systems

Long-Term Security Practices

Regularly update and patch all software and firmware
Conduct security training for employees to recognize and report potential threats

Patching and Updates

Ensure timely installation of security patches provided by Fortinet to mitigate the vulnerability.