CVE-2023-20002: Cisco RoomOS Auth Bypass Vulnerability

CVE-2023-20002 Overview

A Server-Side Request Forgery (SSRF) vulnerability exists in Cisco TelePresence CE and RoomOS Software that could allow an authenticated, local attacker to bypass access controls and conduct SSRF attacks through an affected device. This vulnerability is due to improper validation of user-supplied input in the web application, enabling attackers to send crafted requests that can result in arbitrary network requests being sourced from the affected system.

Critical Impact

An authenticated attacker with local access can leverage this SSRF vulnerability to send arbitrary network requests from the affected Cisco TelePresence or RoomOS device, potentially enabling reconnaissance of internal networks, access to internal services, or pivoting to other systems.

Affected Products

• Cisco RoomOS versions 10.3.2.0, 10.3.4.0, 10.8.2.5, 10.8.4.0, 10.11.3.0, 10.11.5.2, 10.15.3.0
• Cisco TelePresence Collaboration Endpoint versions 8.1.1 through 9.15.10.8
• Multiple firmware releases across Cisco video conferencing endpoints

Discovery Timeline

• 2023-01-20 - CVE-2023-20002 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-20002

Vulnerability Analysis

This vulnerability falls under CWE-918 (Server-Side Request Forgery), a weakness class where an application can be manipulated to initiate requests to arbitrary destinations. In the context of Cisco TelePresence CE and RoomOS, the flaw resides in the web application component that processes user-supplied input without adequate validation.

The authentication requirement means an attacker must first obtain valid credentials or local access to the device. However, once authenticated, the improper input validation allows the attacker to craft malicious requests that the server processes and forwards to attacker-specified destinations. This effectively turns the Cisco endpoint into a proxy for network reconnaissance or attacks against internal resources that would otherwise be unreachable.

Root Cause

The root cause of CVE-2023-20002 is improper validation of user-supplied input within the web application interface of Cisco TelePresence CE and RoomOS Software. The application fails to adequately sanitize or restrict URL parameters and request destinations, allowing authenticated users to specify arbitrary network targets. This lack of server-side validation enables the SSRF condition where the device will initiate HTTP requests on behalf of the attacker.

Attack Vector

The attack requires local access with valid authentication credentials. Once authenticated to the web application, an attacker can submit crafted requests containing malicious URLs or network destinations. The vulnerable component processes these requests without proper validation, causing the Cisco device to:

1. Initiate network connections to attacker-specified internal or external hosts
2. Potentially expose internal services that trust connections from the Cisco endpoint
3. Enable reconnaissance of internal network infrastructure
4. Bypass network segmentation controls by using the device as a pivot point

The attack exploits the trust relationship that internal systems may have with the Cisco video conferencing infrastructure, as these devices are often positioned in network zones with access to sensitive resources.

Detection Methods for CVE-2023-20002

Indicators of Compromise

• Unusual outbound network connections originating from Cisco TelePresence or RoomOS devices to internal services or unexpected external destinations
• Web application access logs showing requests with suspicious URL parameters or non-standard destination addresses
• Network traffic analysis revealing HTTP requests from video conferencing endpoints to internal metadata services, cloud provider APIs, or localhost addresses

Detection Strategies

• Monitor network traffic from Cisco TelePresence and RoomOS devices for connections to internal resources that are not part of normal video conferencing operations
• Review web application logs for authentication events followed by requests containing internal IP addresses, localhost references, or cloud metadata endpoints
• Implement network segmentation monitoring to detect lateral movement attempts originating from video conferencing infrastructure

Monitoring Recommendations

• Deploy network-based intrusion detection rules to identify SSRF patterns in traffic from Cisco endpoints
• Enable verbose logging on the TelePresence and RoomOS web interface and forward logs to a SIEM for correlation analysis
• Establish baseline network behavior for video conferencing devices and alert on deviations such as connections to new internal hosts

How to Mitigate CVE-2023-20002

Immediate Actions Required

• Review and restrict user accounts with access to the TelePresence CE and RoomOS web application to only those who require administrative access
• Implement network segmentation to limit the internal resources reachable from Cisco video conferencing devices
• Monitor for and apply the security patches provided by Cisco
• Audit authentication logs to identify any suspicious access patterns

Patch Information

Cisco has released a security advisory addressing this vulnerability. Administrators should consult the Cisco Security Advisory for detailed patch information and upgrade guidance. It is recommended to update to the latest available firmware versions for both Cisco RoomOS and TelePresence Collaboration Endpoint software that address this SSRF vulnerability.

Workarounds

• Restrict web application access to trusted IP addresses using access control lists on the device or network firewall
• Implement egress filtering on network segments containing Cisco video conferencing devices to limit outbound connection destinations
• Disable unnecessary web-based management interfaces when not actively required for administration
• Use dedicated management VLANs with strict access controls for video conferencing endpoint administration

# Example: Restrict management access via network ACL (conceptual)
# Apply egress filtering on the network segment containing Cisco endpoints
# Limit outbound connections to only required destinations (SIP servers, video bridges)
# Block access to internal metadata services and sensitive infrastructure