CVE-2023-20101: Cisco Emergency Responder Auth Bypass Flaw

CVE-2023-20101 Overview

A critical hardcoded credentials vulnerability exists in Cisco Emergency Responder that could allow an unauthenticated, remote attacker to log in to an affected device using the root account with default, static credentials that cannot be changed or deleted. This vulnerability stems from the presence of static user credentials for the root account that are typically reserved for use during development. A successful exploit could allow an attacker to log in to the affected system and execute arbitrary commands as the root user.

Critical Impact

Unauthenticated remote attackers can gain complete root-level access to Cisco Emergency Responder systems using hardcoded credentials, enabling full system compromise including arbitrary command execution.

Affected Products

• Cisco Emergency Responder
• Cisco Emergency Responder version 12.5(1)SU4

Discovery Timeline

• October 4, 2023 - CVE-2023-20101 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2023-20101

Vulnerability Analysis

This vulnerability (CWE-798: Use of Hard-coded Credentials) represents a severe security flaw in Cisco Emergency Responder where development-reserved static credentials for the root account were inadvertently left in the production software. The root account credentials cannot be changed or deleted by administrators, leaving affected systems permanently vulnerable until patched.

The attack surface is network-accessible, meaning any attacker who can reach the device over the network can attempt authentication using the hardcoded credentials. Once authenticated, the attacker gains full root-level privileges, enabling complete control over the affected system including the ability to execute arbitrary commands, access sensitive data, modify configurations, and potentially pivot to other systems on the network.

Root Cause

The root cause of this vulnerability is the inclusion of static user credentials for the root account in production releases of Cisco Emergency Responder. These credentials were typically reserved for use during development but were not removed or disabled before the software was released. The credentials are hardcoded into the system in a way that prevents administrators from changing or deleting them, making the vulnerability persistent until addressed through a software update.

Attack Vector

The attack vector for CVE-2023-20101 is network-based. An unauthenticated remote attacker can exploit this vulnerability by:

1. Identifying a Cisco Emergency Responder system accessible over the network
2. Attempting to authenticate using the known hardcoded root credentials
3. Upon successful authentication, gaining full root-level access to the system
4. Executing arbitrary commands with root privileges, potentially compromising sensitive emergency response data and infrastructure

The vulnerability requires no user interaction and can be exploited with low complexity, making it particularly dangerous for exposed systems. Since this involves hardcoded credentials in a critical emergency response platform, the potential impact on public safety infrastructure is significant.

Detection Methods for CVE-2023-20101

Indicators of Compromise

• Unexpected or unauthorized login attempts to the root account on Cisco Emergency Responder systems
• Authentication logs showing successful root account logins from unknown or external IP addresses
• Unusual command execution patterns or system modifications under the root account
• Network traffic indicating remote access attempts to Emergency Responder management interfaces

Detection Strategies

• Monitor authentication logs for root account login attempts, particularly from external or unexpected source IP addresses
• Implement network intrusion detection rules to alert on connection attempts to Cisco Emergency Responder management ports
• Deploy SIEM correlation rules to identify patterns of credential-based attacks targeting Emergency Responder systems
• Conduct regular vulnerability scanning to identify unpatched Cisco Emergency Responder instances

Monitoring Recommendations

• Enable comprehensive logging for all authentication events on Cisco Emergency Responder systems
• Configure real-time alerting for any successful root account authentication
• Monitor network traffic to and from Emergency Responder systems for anomalous patterns
• Implement baseline monitoring for system processes and commands executed under the root account

How to Mitigate CVE-2023-20101

Immediate Actions Required

• Identify all Cisco Emergency Responder installations in your environment and verify version numbers
• Apply the security patch from Cisco immediately to all affected systems
• Restrict network access to Cisco Emergency Responder management interfaces using firewall rules or network segmentation
• Review authentication logs for any signs of prior exploitation

Patch Information

Cisco has released a security patch to address this vulnerability. Organizations should immediately consult the Cisco Security Advisory for detailed patch information and upgrade instructions. The patch removes or disables the hardcoded credentials, eliminating the vulnerability. Given the critical nature of this vulnerability and the potential impact on emergency response infrastructure, patching should be prioritized.

Workarounds

• Implement strict network segmentation to limit access to Cisco Emergency Responder management interfaces
• Deploy firewall rules to restrict remote access to Emergency Responder systems from untrusted networks
• Enable enhanced logging and monitoring while awaiting patch deployment
• Consider temporarily isolating affected systems from external network access if immediate patching is not possible

# Example network segmentation approach
# Restrict access to Emergency Responder management interface
# Add firewall rules to limit access to trusted administrator IPs only
iptables -A INPUT -p tcp --dport 443 -s trusted_admin_network -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP