CVE-2020-36925 Overview
CVE-2020-36925 is a session hijacking vulnerability affecting Arteco Web Client DVR/NVR systems. The vulnerability stems from insufficient session ID complexity, which allows remote attackers to bypass authentication mechanisms. By exploiting this weakness, attackers can brute force session IDs within a specific numeric range to obtain valid sessions and gain unauthorized access to live camera streams and surveillance footage.
Critical Impact
Unauthorized remote access to video surveillance systems, exposing live camera feeds and recorded footage to attackers without authentication.
Affected Products
- Arteco Web Client DVR/NVR
Discovery Timeline
- 2026-01-06 - CVE CVE-2020-36925 published to NVD
- 2026-01-08 - Last updated in NVD database
Technical Details for CVE-2020-36925
Vulnerability Analysis
This vulnerability is classified under CWE-331 (Insufficient Entropy), which indicates that the session management implementation uses session identifiers with inadequate randomness. The Arteco Web Client DVR/NVR system generates session IDs using a predictable numeric range rather than cryptographically secure random values. This design flaw makes it computationally feasible for attackers to enumerate and guess valid session identifiers through brute force attacks.
The network-accessible nature of this vulnerability means any attacker with network connectivity to the affected system can attempt exploitation without requiring prior authentication or user interaction. Once a valid session ID is discovered, the attacker inherits all privileges associated with that session, potentially including administrative access to the surveillance system.
Root Cause
The root cause is the use of insufficient entropy in session ID generation (CWE-331). The application generates session identifiers from a limited numeric keyspace rather than using cryptographically secure pseudo-random number generators (CSPRNGs). This results in session IDs that are predictable and susceptible to brute force attacks. Proper session management requires session IDs with at least 128 bits of entropy generated from a CSPRNG to make brute force attacks computationally infeasible.
Attack Vector
The attack is conducted remotely over the network. An attacker can systematically iterate through the limited range of possible session ID values, submitting each candidate to the web interface. When a valid session ID is discovered, the attacker gains immediate access to the authenticated session without needing valid credentials. This allows bypassing authentication entirely and accessing sensitive surveillance data including live camera streams.
The attack requires no user interaction and can be automated using simple scripting tools. The limited keyspace of session IDs means a successful attack can be completed in a relatively short timeframe depending on network latency and rate limiting controls.
Detection Methods for CVE-2020-36925
Indicators of Compromise
- Unusually high volume of HTTP requests with sequential or patterned session ID values
- Multiple failed authentication attempts followed by successful session access from the same source IP
- Anomalous session access patterns where sessions are accessed without corresponding login events
- Access to surveillance streams from unexpected geographic locations or IP ranges
Detection Strategies
- Monitor web server access logs for brute force patterns targeting session endpoints
- Implement rate limiting detection to identify sources exceeding normal request thresholds
- Deploy network intrusion detection signatures for session enumeration attack patterns
- Configure SIEM rules to correlate session access events with authentication logs
Monitoring Recommendations
- Enable detailed logging for all session creation and validation events on the DVR/NVR system
- Implement real-time alerting for session access attempts that bypass normal authentication flow
- Monitor for unauthorized access to camera streams during off-hours or from non-standard access points
- Review access logs regularly for evidence of session ID enumeration attempts
How to Mitigate CVE-2020-36925
Immediate Actions Required
- Restrict network access to the Arteco Web Client interface using firewall rules or VPN requirements
- Implement IP whitelisting to limit access to trusted administrative hosts only
- Enable aggressive rate limiting on authentication and session validation endpoints
- Deploy a Web Application Firewall (WAF) with brute force protection capabilities
Patch Information
Contact Arteco directly through Arteco Global Homepage for information on available security updates and patches for this vulnerability. Organizations should verify their current software version and apply any available security updates that address session management weaknesses.
Additional technical details about this vulnerability can be found at the VulnCheck Arteco DVNVR Advisory, Zero Science Vulnerability ZSL-2020-5613, and Exploit-DB #49348.
Workarounds
- Place the DVR/NVR system behind a VPN and require VPN authentication before web interface access
- Deploy a reverse proxy with additional authentication layers in front of the vulnerable application
- Implement network segmentation to isolate surveillance systems from general network traffic
- Configure session timeout values to the minimum acceptable duration to reduce attack window
# Example: Network segmentation using iptables to restrict access
# Allow access only from trusted management network
iptables -A INPUT -p tcp --dport 80 -s 10.10.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 10.10.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
