CVE-2020-36920: iDS6 DSSPro Privilege Escalation Flaw

CVE-2020-36920 Overview

CVE-2020-36920 is an improper access control vulnerability affecting iDS6 DSSPro Digital Signage System version 6.2. The vulnerability allows authenticated users to elevate their privileges through console JavaScript functions, enabling attackers to create users, modify roles and permissions, and potentially achieve full application takeover by exploiting insecure direct object references.

This privilege escalation vulnerability is classified as CWE-863 (Incorrect Authorization), which occurs when software does not properly enforce authorization checks, allowing users to perform actions or access resources beyond their intended privileges.

Critical Impact

Authenticated attackers can escalate privileges to administrator level, create new users, modify roles and permissions, and potentially achieve complete application takeover through insecure direct object references.

Affected Products

• iDS6 DSSPro Digital Signage System 6.2

Discovery Timeline

• 2026-01-06 - CVE CVE-2020-36920 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2020-36920

Vulnerability Analysis

This vulnerability stems from insufficient authorization enforcement within the iDS6 DSSPro Digital Signage System web application. The application fails to properly validate user permissions when processing requests through browser-accessible JavaScript functions, allowing lower-privileged authenticated users to invoke administrative operations.

The attack is network-accessible and requires only low-privileged authentication to exploit. Once authenticated, an attacker can leverage the browser's developer console to directly call privileged JavaScript functions that should be restricted to administrator accounts. The lack of server-side authorization checks means the application trusts client-side function calls without verifying the requesting user's actual permission level.

The vulnerability enables attackers to perform unauthorized actions including creating new user accounts, modifying existing user roles and permissions, and accessing administrative features. This can lead to a complete compromise of the digital signage system's access control model and potentially enable persistent backdoor access.

Root Cause

The root cause of CVE-2020-36920 is the application's reliance on client-side access controls without corresponding server-side authorization validation. The iDS6 DSSPro system exposes privileged JavaScript functions in the browser console that directly communicate with backend APIs. When these functions are invoked, the server fails to verify whether the authenticated user possesses the necessary role or permissions to execute the requested operation, treating all authenticated requests equally regardless of privilege level.

Attack Vector

The attack vector is network-based, requiring an attacker to have valid low-level credentials to the iDS6 DSSPro system. Once authenticated, the attacker can open the browser's developer console and invoke privileged JavaScript functions directly. These functions make API calls to the backend server, which processes them without proper authorization checks.

The attack flow involves:

1. Authenticating to the iDS6 DSSPro system with a low-privileged account
2. Opening the browser's developer console (F12)
3. Identifying and invoking privileged JavaScript functions exposed in the application
4. Executing unauthorized operations such as user creation or permission modification

For detailed technical analysis and proof-of-concept information, refer to the Zero Science Vulnerability Advisory ZSL-2020-5608 and Exploit-DB #48992.

Detection Methods for CVE-2020-36920

Indicators of Compromise

• Unexpected user account creation or modifications in the iDS6 DSSPro administrative logs
• API calls to user management endpoints from non-administrator sessions
• Browser console activity logs showing direct invocation of administrative JavaScript functions
• Unauthorized changes to user roles or permissions without corresponding admin audit entries

Detection Strategies

• Monitor API endpoint access patterns to identify privilege escalation attempts from low-privileged users
• Implement logging for all user management operations and alert on anomalous activity patterns
• Deploy web application firewalls (WAF) to detect and block unauthorized API requests to administrative endpoints
• Review iDS6 DSSPro application logs for user creation or permission modification events that don't correlate with administrator sessions

Monitoring Recommendations

• Enable comprehensive audit logging for all authentication and authorization events within the digital signage system
• Configure alerts for any user account changes or permission modifications performed outside normal administrative workflows
• Monitor network traffic to the iDS6 DSSPro server for unusual API call patterns or elevated request volumes to sensitive endpoints

How to Mitigate CVE-2020-36920

Immediate Actions Required

• Restrict network access to iDS6 DSSPro systems to trusted networks and administrators only
• Review and audit all existing user accounts for unauthorized accounts or privilege escalations
• Implement network-level access controls to limit who can authenticate to the system
• Consider temporarily disabling the system if it handles sensitive content until proper mitigations are in place

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations should contact the vendor directly for remediation guidance and monitor security advisories for updates. Additional technical details can be found in the VulnCheck Advisory and IBM X-Force Vulnerability #191260.

Workarounds

• Implement a reverse proxy or web application firewall in front of the iDS6 DSSPro system to enforce server-side authorization checks
• Restrict access to the digital signage system to only trusted administrators and networks
• Disable or block access to browser developer tools through endpoint management solutions where possible
• Segment the iDS6 DSSPro system on an isolated network with strict access controls

# Network segmentation example - restrict access to iDS6 DSSPro system
# Add firewall rules to limit access to trusted administrator IPs only
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP