CVE-2025-52026: Aptsys gemscms Information Disclosure Flaw

CVE-2025-52026 Overview

An information disclosure vulnerability exists in the /srvs/membersrv/getCashiers endpoint of the Aptsys gemscms backend platform through 2025-05-28. This unauthenticated endpoint returns a list of cashier accounts, including names, email addresses, usernames, and passwords hashed using MD5. As MD5 is a broken cryptographic function, the hashes can be easily reversed using public tools, exposing user credentials in plaintext. This allows remote attackers to perform unauthorized logins and potentially gain access to sensitive POS operations or backend functions.

Critical Impact

Unauthenticated attackers can retrieve cashier credentials including MD5-hashed passwords, enabling unauthorized access to POS systems and sensitive backend operations.

Affected Products

• Aptsys gemscms backend platform (through 2025-05-28)

Discovery Timeline

• 2026-01-23 - CVE CVE-2025-52026 published to NVD
• 2026-01-26 - Last updated in NVD database

Technical Details for CVE-2025-52026

Vulnerability Analysis

This information disclosure vulnerability (CWE-200) affects the Aptsys gemscms backend platform, specifically the /srvs/membersrv/getCashiers API endpoint. The endpoint lacks proper authentication controls, allowing any remote attacker to access sensitive user account data without credentials. The exposed data includes personally identifiable information (PII) such as names and email addresses, along with usernames and password hashes.

The fundamental security flaw is compounded by the use of MD5 for password hashing. MD5 has been considered cryptographically broken since the mid-2000s due to collision vulnerabilities and the availability of rainbow tables containing precomputed hashes for common passwords. This makes reversing the exposed hashes trivial using publicly available tools and databases.

Root Cause

The root cause of this vulnerability is twofold: first, the /srvs/membersrv/getCashiers endpoint is exposed without requiring authentication, violating the principle of least privilege. Second, the application uses the deprecated MD5 hashing algorithm for password storage instead of modern, secure alternatives such as bcrypt, Argon2, or PBKDF2. This combination of missing access controls and weak cryptography creates a direct path from unauthenticated access to credential compromise.

Attack Vector

The attack is network-based and requires no authentication or user interaction. An attacker can simply send an HTTP request to the vulnerable endpoint to retrieve the list of cashier accounts. Once the MD5 password hashes are obtained, the attacker can use rainbow tables, hash databases, or GPU-accelerated cracking tools to recover plaintext passwords. With valid credentials, the attacker can then authenticate to the system and potentially access sensitive POS operations, financial data, or perform unauthorized transactions.

The attack flow involves sending a GET or POST request to the /srvs/membersrv/getCashiers endpoint, parsing the JSON response containing user data, extracting MD5 hashes, and using lookup services or cracking tools to obtain plaintext passwords.

Detection Methods for CVE-2025-52026

Indicators of Compromise

• Unusual or unauthorized HTTP requests to the /srvs/membersrv/getCashiers endpoint from external IP addresses
• Multiple failed or successful login attempts using cashier accounts from unfamiliar locations or IP addresses
• Evidence of bulk data retrieval from membership service endpoints in web server logs
• Unexpected access to POS administrative functions by cashier-level accounts

Detection Strategies

• Monitor web application logs for requests to the /srvs/membersrv/getCashiers endpoint, especially from unauthenticated sessions
• Implement alerting on repeated access attempts to sensitive API endpoints from single IP addresses
• Deploy web application firewalls (WAF) with rules to detect and block unauthenticated access to membership service endpoints
• Review authentication logs for login attempts using credentials that may have been exposed

Monitoring Recommendations

• Enable detailed logging for all API endpoints in the gemscms platform
• Configure SIEM rules to correlate unauthenticated API access with subsequent authentication events
• Monitor for MD5 hash lookups or password cracking activity originating from internal network segments
• Implement user behavior analytics to detect anomalous cashier account activity

How to Mitigate CVE-2025-52026

Immediate Actions Required

• Restrict access to the /srvs/membersrv/getCashiers endpoint by implementing authentication and authorization controls
• Force password resets for all cashier accounts that may have been exposed
• Migrate password storage from MD5 to a secure hashing algorithm such as bcrypt or Argon2
• Review access logs to identify potential exploitation and compromised accounts
• Consider temporarily disabling the vulnerable endpoint until a patch is applied

Patch Information

Check with the vendor at APTSys for available security patches or updated versions of the gemscms platform. Technical details about this vulnerability can be found in the GitHub Gist documentation.

Workarounds

• Implement network-level access controls to restrict the /srvs/membersrv/getCashiers endpoint to authorized IP ranges only
• Deploy a reverse proxy or WAF rule to block unauthenticated requests to the vulnerable endpoint
• If possible, disable the endpoint entirely until authentication can be properly implemented
• Implement rate limiting on API endpoints to slow down bulk data harvesting attempts
• Enable IP-based monitoring and automatic blocking for suspicious access patterns

# Example: Block unauthenticated access to vulnerable endpoint via nginx
location /srvs/membersrv/getCashiers {
    # Deny all access until authentication is implemented
    deny all;
    return 403;
}