CVE-2025-25211: CHOCO TEI WATCHER Auth Bypass Vulnerability

CVE-2025-25211 Overview

A weak password requirements vulnerability exists in the CHOCO TEI WATCHER mini (IB-MCT001), an industrial production line camera device manufactured by Inaba Denki Sangyo. This vulnerability affects all versions of the device and allows attackers to perform brute-force attacks against the authentication mechanism, potentially gaining unauthorized access to the system.

The CHOCO TEI WATCHER mini is designed for monitoring production lines and recording stoppage events in industrial environments. Due to insufficient password complexity requirements (CWE-521), the device's authentication system is susceptible to credential guessing attacks, which could allow malicious actors to compromise the device and potentially disrupt industrial operations or conduct surveillance.

Critical Impact

Successful exploitation enables unauthorized access to industrial camera systems, potentially allowing attackers to conduct remote surveillance, tamper with recordings, or disrupt production line monitoring capabilities.

Affected Products

• CHOCO TEI WATCHER mini (IB-MCT001) - All versions
• Inaba Denki Sangyo production line monitoring devices
• Industrial camera systems using vulnerable firmware

Discovery Timeline

• March 31, 2025 - CVE-2025-25211 published to NVD
• April 1, 2025 - Last updated in NVD database

Technical Details for CVE-2025-25211

Vulnerability Analysis

This vulnerability stems from inadequate password policy enforcement in the CHOCO TEI WATCHER mini device. The authentication mechanism does not require sufficiently complex passwords, making the system vulnerable to brute-force attacks. The vulnerability is network-accessible, requires no privileges or user interaction to exploit, and can result in complete compromise of confidentiality, integrity, and availability of the affected system.

According to the CISA ICS Advisory ICSA-25-084-04, this vulnerability affects critical infrastructure environments where these production line cameras are deployed. The Nozomi Networks research highlights that unpatched vulnerabilities in these devices may allow remote surveillance and hinder stoppage recording functionality.

Root Cause

The root cause of CVE-2025-25211 is the implementation of weak password requirements (CWE-521) in the device's authentication system. The firmware does not enforce minimum password length, complexity requirements, or account lockout mechanisms that would prevent automated credential guessing attacks. This design flaw allows attackers to systematically attempt password combinations until valid credentials are discovered.

Attack Vector

The attack vector for this vulnerability is network-based, meaning an attacker with network access to the vulnerable device can attempt exploitation remotely. The attack requires no authentication (privileges) and no user interaction, making it particularly dangerous in industrial environments where these devices may be accessible on internal networks or, in some cases, exposed to the internet.

An attacker would typically perform the following attack sequence:

1. Identify network-accessible CHOCO TEI WATCHER mini devices through network scanning
2. Enumerate the authentication interface of the target device
3. Launch automated brute-force attacks using common password dictionaries or sequential password generation
4. Gain unauthorized access upon successful credential discovery
5. Leverage access to conduct surveillance, manipulate recordings, or disrupt operations

Detection Methods for CVE-2025-25211

Indicators of Compromise

• Multiple failed authentication attempts from single or multiple source IP addresses targeting IB-MCT001 devices
• Unusual login patterns or successful authentication from unexpected geographic locations or IP ranges
• Abnormal access patterns to camera feeds or configuration interfaces outside of normal operational hours
• Changes to device configuration or password settings that were not authorized by administrators

Detection Strategies

• Implement network monitoring to detect brute-force attack patterns against industrial camera devices
• Deploy intrusion detection systems (IDS) with rules to identify authentication spray attacks targeting IoT/ICS devices
• Monitor authentication logs for excessive failed login attempts followed by successful authentication
• Use SentinelOne Singularity platform to monitor network traffic patterns and identify anomalous behavior targeting industrial devices

Monitoring Recommendations

• Enable logging on all CHOCO TEI WATCHER mini devices and forward logs to a centralized SIEM solution
• Configure alerting thresholds for failed authentication attempts exceeding normal operational baselines
• Implement network segmentation monitoring to detect unauthorized access attempts to ICS/OT network segments
• Regularly audit access logs and user accounts on vulnerable devices to identify potential compromise

How to Mitigate CVE-2025-25211

Immediate Actions Required

• Isolate CHOCO TEI WATCHER mini devices from direct internet access and restrict access to authorized internal networks only
• Implement strong, unique passwords on all affected devices even if the device does not enforce complexity requirements
• Deploy network-level access controls such as firewalls and VLANs to limit exposure of vulnerable devices
• Enable account lockout mechanisms at the network level if available through upstream security appliances
• Review and audit all existing user accounts and credentials on affected devices

Patch Information

As of the last update, no official patch has been released that addresses this vulnerability. According to the Inaba vulnerability disclosure, all versions of the CHOCO TEI WATCHER mini (IB-MCT001) are affected. Organizations should monitor the vendor's communications and the JVN Vulnerability Report for updates regarding security patches or firmware updates.

Workarounds

• Implement network segmentation to isolate vulnerable devices from untrusted network segments
• Deploy a VPN or jump host requirement for accessing industrial camera systems remotely
• Configure upstream firewall rules to limit source IP addresses that can connect to device management interfaces
• Implement intrusion prevention systems (IPS) with rate limiting to block brute-force attack attempts
• Consider deploying a reverse proxy with additional authentication requirements in front of vulnerable devices

# Example network segmentation using iptables
# Restrict access to IB-MCT001 device to specific management subnet
iptables -A INPUT -p tcp --dport 80 -s 10.10.50.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 10.10.50.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP