CVE-2025-12866: EIP Plus Auth Bypass Vulnerability

CVE-2025-12866 Overview

EIP Plus developed by Hundred Plus contains a Weak Password Recovery Mechanism vulnerability (CWE-640) that allows unauthenticated remote attackers to predict or brute-force the "forgot password" link, thereby successfully resetting any user's password. This authentication bypass vulnerability enables complete account takeover without requiring any prior authentication or user interaction.

Critical Impact

Unauthenticated attackers can remotely reset any user's password through predictable password reset tokens, leading to complete account compromise and unauthorized system access.

Affected Products

• EIP Plus by Hundred Plus (all versions prior to patch)

Discovery Timeline

• November 10, 2025 - CVE-2025-12866 published to NVD
• November 12, 2025 - Last updated in NVD database

Technical Details for CVE-2025-12866

Vulnerability Analysis

This vulnerability stems from a weak password recovery mechanism in the EIP Plus application. The password reset functionality generates predictable tokens or links that can be guessed or brute-forced by attackers. When users request a password reset, the system creates a reset link containing a token that lacks sufficient entropy or randomness, making it susceptible to prediction attacks.

The vulnerability allows network-based attacks with low complexity, requiring no privileges or user interaction. Successful exploitation results in complete compromise of confidentiality, integrity, and availability of the affected system, as attackers can gain unauthorized access to any user account including administrative accounts.

Root Cause

The root cause is the implementation of a weak password recovery mechanism (CWE-640) where the password reset tokens are generated using predictable algorithms or insufficient randomness. This could include sequential token generation, time-based tokens with low precision, or tokens derived from predictable user attributes. The system fails to implement adequate entropy in token generation and lacks proper rate limiting or token expiration controls.

Attack Vector

The attack vector is network-based, allowing remote exploitation. An attacker can target the password reset functionality by:

1. Initiating multiple password reset requests for target accounts
2. Analyzing the structure and pattern of generated reset tokens
3. Predicting or brute-forcing valid reset tokens based on identified patterns
4. Using the predicted token to access the password reset page and set a new password
5. Gaining complete access to the victim's account

The attack requires no authentication, no user interaction, and can be automated to compromise multiple accounts systematically. For technical details on the vulnerability mechanism, refer to the TW-CERT Security Advisory.

Detection Methods for CVE-2025-12866

Indicators of Compromise

• Multiple password reset requests originating from a single IP address or targeting specific accounts
• Successful password reset completions without corresponding legitimate user activity
• Unusual patterns in password reset token usage, such as sequential token attempts
• Authentication logs showing successful logins immediately following password resets from unfamiliar locations

Detection Strategies

• Monitor for anomalous volume of password reset requests across the application
• Implement alerting for multiple failed password reset token validation attempts
• Track correlation between password reset events and subsequent login activity from new IP addresses
• Deploy web application firewall (WAF) rules to detect brute-force patterns against reset endpoints

Monitoring Recommendations

• Enable detailed logging for all password reset requests including IP addresses, timestamps, and user agents
• Configure SIEM rules to alert on password reset request spikes or unusual access patterns
• Monitor for authentication events that follow password resets, especially from previously unseen locations
• Review access logs for patterns indicating automated or scripted attacks against the forgot password functionality

How to Mitigate CVE-2025-12866

Immediate Actions Required

• Disable the password reset functionality temporarily until a patch is applied
• Implement additional authentication factors for password recovery (e.g., security questions, email verification codes)
• Deploy rate limiting on the password reset endpoint to prevent brute-force attacks
• Review recent password reset logs for signs of exploitation and force password resets for potentially compromised accounts
• Contact Hundred Plus for official patch availability and upgrade guidance

Patch Information

Organizations should consult the official vendor advisory and the TW-CERT Security Advisory for patch availability and update instructions. Additional information is available from the CHT Security News Update. Apply the latest security patches from Hundred Plus as soon as they become available.

Workarounds

• Implement a Web Application Firewall (WAF) with rules to block rapid password reset attempts and enforce rate limiting
• Add CAPTCHA or similar challenge-response mechanisms to the password reset flow
• Require multi-factor authentication for password recovery operations
• Disable self-service password reset and require manual administrator-assisted password recovery
• Implement IP-based blocking for repeated failed reset attempts

# Example: Rate limiting configuration for nginx to protect password reset endpoint
# Add to nginx server block configuration

location /forgot-password {
    limit_req zone=password_reset burst=5 nodelay;
    limit_req_status 429;
    proxy_pass http://backend;
}

# Define rate limit zone in http block
# limit_req_zone $binary_remote_addr zone=password_reset:10m rate=2r/m;