CVE-2020-37144: Exagate SYSGuard 6001 CSRF Vulnerability

CVE-2020-37144 Overview

Exagate SYSGuard 6001 contains a cross-site request forgery (CSRF) vulnerability that allows attackers to create unauthorized admin accounts through a crafted HTML form. Attackers can trick authenticated users into submitting a malicious form to /kulyon.php that adds a new user with administrative privileges without the victim's consent. This vulnerability represents a significant security risk for organizations relying on SYSGuard 6001 for system monitoring and management.

Critical Impact

Successful exploitation allows attackers to gain full administrative control over the Exagate SYSGuard 6001 device by creating rogue administrator accounts without user authorization.

Affected Products

• Exagate SYSGuard 6001

Discovery Timeline

• 2026-02-05 - CVE CVE-2020-37144 published to NVD
• 2026-02-05 - Last updated in NVD database

Technical Details for CVE-2020-37144

Vulnerability Analysis

This vulnerability is classified as Cross-Site Request Forgery (CSRF), identified by CWE-352. The Exagate SYSGuard 6001 web interface fails to implement proper CSRF protections on the user management endpoint (/kulyon.php). When an authenticated administrator visits a malicious webpage containing a specially crafted HTML form, the form automatically submits a request to create a new administrative user on the SYSGuard device. The attack requires user interaction—the victim must visit the attacker-controlled page while having an active authenticated session with the SYSGuard management interface.

Root Cause

The root cause of this vulnerability is the absence of anti-CSRF tokens in the user creation functionality of the SYSGuard 6001 web interface. The /kulyon.php endpoint processes administrative requests without validating whether the request originated from a legitimate source within the application. Without CSRF tokens or other origin validation mechanisms, the application cannot distinguish between legitimate user-initiated requests and forged requests from malicious third-party websites.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker constructs a malicious HTML page containing a hidden form that targets the /kulyon.php endpoint on the victim's SYSGuard 6001 device. The form is pre-populated with parameters to create a new administrative user with attacker-specified credentials. When an authenticated administrator visits the malicious page, the form is automatically submitted via JavaScript or through social engineering tactics. The SYSGuard device processes the request as legitimate since it comes from the administrator's authenticated browser session, resulting in the creation of an unauthorized admin account.

The attack does not require the attacker to have any prior access to the target system. They only need to know or guess the internal IP address of the SYSGuard device and entice the victim to visit their malicious page. Technical details and proof-of-concept information can be found at the Exploit-DB #48234 and the VulnCheck Advisory on Exagate.

Detection Methods for CVE-2020-37144

Indicators of Compromise

• Unexpected new administrator accounts appearing in the SYSGuard 6001 user management interface
• HTTP POST requests to /kulyon.php with user creation parameters originating from external referrers
• Web server logs showing requests to user management endpoints with suspicious or external Referer headers
• Unusual login activity from newly created accounts that were not authorized by legitimate administrators

Detection Strategies

• Monitor web server access logs for POST requests to /kulyon.php and correlate with Referer header analysis to identify requests originating from external domains
• Implement web application firewall (WAF) rules to detect and block requests to sensitive administrative endpoints that lack proper origin headers
• Deploy network monitoring to identify cross-origin requests targeting internal SYSGuard management interfaces

Monitoring Recommendations

• Enable detailed access logging on the SYSGuard 6001 device to capture all administrative actions
• Regularly audit user accounts on the device to detect unauthorized additions
• Implement network segmentation to isolate management interfaces from general user traffic
• Configure alerts for any user creation events on the SYSGuard platform

How to Mitigate CVE-2020-37144

Immediate Actions Required

• Restrict access to the SYSGuard 6001 management interface to trusted internal networks only
• Implement network-level access controls (firewall rules, VPN requirements) to limit who can reach the device's web interface
• Audit existing user accounts and remove any unauthorized administrative accounts
• Ensure administrators do not access untrusted websites while authenticated to the SYSGuard management interface

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations should contact Exagate directly to inquire about security updates. Additional information about the affected product can be found at the Exagate Official Website and the archived Exagate SysGuard Report Archive.

Workarounds

• Deploy a reverse proxy with CSRF protection in front of the SYSGuard 6001 web interface to add token-based validation
• Use browser isolation or dedicated browser profiles for administrative tasks to prevent CSRF attacks
• Implement strict SameSite cookie policies at the network level if possible through a web application firewall
• Consider disabling the web management interface entirely and using alternative management methods if available

# Example: Restrict access to SYSGuard management interface via iptables
# Allow only specific trusted management workstation IP
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.100 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.100 -j ACCEPT
# Deny all other access to web management ports
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP