Critical
CVSS 8.1 Information Disclosure Responsible Disclosure
Disclosure
WebAuthn Passkey Credential ID Mass Leakage
Passkey credential IDs returned enumerably enabling fingerprinting and replay scenarios across 2FA system.
- Target
- African Crypto Exchange
- Category
- Information Disclosure
- 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.