CVE-2021-36191 Explained : Impact and Mitigation
Learn about CVE-2021-36191, a URL redirection vulnerability in Fortinet FortiWeb versions 6.4.1 and below, impacting device security and integrity. Understand the impact, technical details, and mitigation steps.
A URL redirection vulnerability in Fortinet FortiWeb versions allows attackers to manipulate GET parameters and use the device as a proxy.
Understanding CVE-2021-36191
This CVE describes a security issue in Fortinet FortiWeb that enables attackers to redirect URLs to untrusted sites, potentially leveraging the device for malicious purposes.
What is CVE-2021-36191?
The vulnerability in Fortinet FortiWeb versions 6.4.1 and below, 6.3.15 and below allows for open redirection attacks. By crafting specific GET parameters in requests to error handlers, an attacker can abuse the device as a proxy.
The Impact of CVE-2021-36191
With a base score of 4.1 (Medium severity), this CVE poses a risk for organizations using affected FortiWeb versions. Attackers can exploit this vulnerability to carry out various malicious activities, potentially compromising system integrity.
Technical Details of CVE-2021-36191
This section covers the vulnerability description, affected systems and versions, as well as the exploitation mechanism.
Vulnerability Description
The CVE involves a URL redirection flaw in Fortinet FortiWeb, allowing attackers to redirect URLs to untrusted sites through crafted GET parameters.
Affected Systems and Versions
FortiWeb versions 6.4.1 and below, as well as 6.3.15 and below, are impacted by this vulnerability.
Exploitation Mechanism
Attackers exploit this vulnerability by manipulating GET parameters in requests to error handlers, enabling them to misuse the FortiWeb device as a proxy.
Mitigation and Prevention
In mitigating CVE-2021-36191, organizations should take immediate protective measures and establish long-term security practices.
Immediate Steps to Take
Security teams should apply vendor patches promptly, monitor for unusual activities, and restrict access to vulnerable FortiWeb devices.
Long-Term Security Practices
Implement network segmentation, regularly update security configurations, and conduct periodic security assessments to prevent similar vulnerabilities.
Patching and Updates
Stay informed about security advisories from Fortinet and promptly apply patches to ensure the protection of FortiWeb devices.