Critical
CVSS 9.8 Broken Authentication Responsible Disclosure
Disclosure
Full Account Takeover via Password Reset Brute Force + XFF Bypass
Any user's password can be reset without authentication, CAPTCHA, or rate limiting. The password reset code brute force endpoint has zero rate limiting -- 300+ consecutive requests were tested with 0 blocked. Combined with X-Forwarded-For bypass, the attack is completely unlimited
- Target
- EU Gaming Key Marketplace
- Category
- Broken Authentication
- 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.