Critical
CVSS 9.6 Access Control Responsible Disclosure
Disclosure
Unauthenticated Invoice API Endpoints (request-void/cancel/mark-as-paid)
7 invoice manipulation endpoints accept requests without any auth token; any UUID enables cancel/refund/mark-paid actions.
- Target
- European Crypto Payment Gateway
- Category
- Access Control
- Channel
- Responsible Disclosure
- Disclosed
- 2026-03
Redaction note
Vendor identity withheld.
This finding is documented here as part of MemCyber’s public disclosure record. The vendor has been anonymized to a sector and region descriptor. Full technical detail — including root cause, reproducible proof-of-concept, remediation guidance, and vendor attribution where granted — is available to qualified prospects under NDA.
Coordinated disclosure
How we handled it.
- Reported to the vendor via Responsible Disclosure with a reproducible proof-of-concept.
- Triage + remediation window coordinated with the vendor security team.
- Fix verified before any public reference.
- This record published only after the embargo period closed.