[CVE-2025-52026] Unauthenticated data exposure in Aptsys gemscms backend
Summary
An unauthenticated information disclosure vulnerability was identified in Aptsys’ gemscms backend platform.
A publicly reachable API used in production deployments returns staff/cashier account records including email addresses, usernames, and password hashes computed with MD5.
Because MD5 is a broken cryptographic function, these hashes are trivially reversible with commonly available tools and databases, enabling account compromise and impersonation.
CVE: CVE-2025-52026 (Reserved - pending public publication)
This public advisory serves as the official reference for CVE publication.
Technical exploitation details and live data are intentionally withheld to reduce risk to end users.
Background & Discovery
The vulnerability was discovered incidentally in May 2025 during normal use of an F&B client’s mobile application that communicates with the Aptsys gemscms backend. The same backend platform is shared among multiple Aptsys client apps, and independent review confirmed an unauthenticated data exposure affecting all connected deployments.
Multiple attempts to responsibly disclose the issue to the vendor were made through multiple channels between May-Nov 2025, but no remediation or formal acknowledgment was received.
Affected Product(s)
- Vendor: Aptsys
- Product: Aptsys gemscms POS Platform (backend) — used by multiple F&B clients
- Component: Staff/cashier management API (specific endpoint withheld)
- Confirmed Affected: Production environment verified in May 2025
- Versions: Unknown (likely affects multiple active backend deployments)
Vulnerability Details
A remote unauthenticated API call to a staff-listing endpoint in the backend returns JSON-formatted records containing:
- Email addresses
- Usernames
- Password hashes computed using MD5
As MD5 is an obsolete and cryptographically insecure hash function, these hashes can be easily reversed via public lookup databases, resulting in plaintext password recovery.
This flaw constitutes an information disclosure vulnerability with a direct risk of account takeover and potential privilege escalation in connected POS and backend systems.
Exploitation (High-Level)
- Attack vector: Remote
- Authentication required: None
- Complexity: Low
A remote attacker can access the affected API endpoint without any authentication, retrieve exposed account data, and recover passwords from MD5 hashes using publicly available cracking services.
Note: Concrete API paths, live responses, and PoC code are intentionally withheld to prevent weaponization of this issue.
Impact
- Unauthorized disclosure of staff and cashier account data
- Exposure of credential material leading to plaintext password recovery
- Potential unauthorized access to POS operations and backend administrative functions
- Real-world compromise risk across multiple deployed instances
Mitigation & Recommendations
For Operators / Administrators
- Restrict access to staff-listing endpoints to internal networks or VPN.
- Enforce authentication and access control for all backend API routes.
- Replace MD5 password hashing with a modern algorithm such as Argon2, bcrypt, or scrypt.
- Reset exposed passwords and enforce password rotation for all affected users.
- Enable MFA for administrative and high-privilege accounts.
- Review logs for unauthorized access and password reuse indicators.
- Conduct security review of all API endpoints to ensure proper authentication and data minimization.
For Developers / Vendor
- Remove sensitive credential fields (password hashes) from all API responses.
- Add access-control verification and session enforcement.
- Implement rate limiting and centralized audit logging.
Timeline
- May 2025: Vulnerability discovered and verified in production deployment
- May-Nov 2025: Multiple disclosure attempts made to Aptsys without remediation
- Jul 2025: CVE ID reserved (CVE-2025-52026)
- Nov 2025: Public disclosure published (this advisory)
Status
- Vendor response: No acknowledgment or fix confirmed as of November 2025
- CVE status: RESERVED → Pending PUBLIC upon MITRE confirmation
- Technical details: Redacted; available under NDA/PGP for vendor or CERT coordination
Withheld Information
To reduce risk of exploitation, the following are intentionally omitted:
- Specific API request/response payloads
- Live or production server URLs
- Proof-of-concept code or automation scripts
- Real user identifiers, email addresses, or password hashes
Operators of Aptsys gemscms deployments should treat this as a high-severity issue and apply mitigations immediately. Vendors and CERT teams may contact the reporter for full technical details.