Critical
CVSS 10.0 S3 Misconfig Responsible Disclosure
Disclosure
[vendor] S3 Bucket Full Compromise - Deep Exfiltration Proof
Target: [vendor] Asset: AWS S3 Bucket [vendor] (us-west-2) Status: VERIFIED - Full R/W/D Access Proven
- Target
- EU Crypto Exchange
- Category
- S3 Misconfig
- Channel
- Responsible Disclosure
- Disclosed
- 2026-04
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.