EUC-EO case studies
EUC-EO · Put your knowledge to work in context.
The EC-Council Certified Encryption Specialist (EUC-EO, also called ECES) is a vendor-neutral credential aimed at practitioners who need working knowledge of cryptography rather than pure theory. Typical candidates are security analysts, system and network administrators, developers who implement crypto, and auditors who must judge whether a design is sound. The EUC-EO case studies are 5 cases and about 3,803 words.
1Identical Backup Blocks and a Restore Oracle
A SaaS provider stores tenant backups with AES-256-CBC in a custom Java service. All tenants share one 256-bit data key compiled into the configuration; the IV is a fixed 16-byte constant, and PKCS#7 padding is used.
747 words, about 4 min2The Ten-Year Root and the Unrecoverable Revocation Path
A retailer operates an internal two-tier PKI. The offline root CA has a 20-year self-signed certificate using RSA-2048 with SHA-1; it has issued one subordinate CA with a 10-year certificate.
798 words, about 4 min3TLS 1.0 at the Payment Load Balancer
A payment processor terminates TLS at a hardware load balancer. The listener supports TLS 1.0, 1.1, and 1.2; cipher suites include RSA key exchange and AES-CBC; DHE parameters are 1024-bit; the certificate is a public wildcard .payments.example.com with CN set but no subjectAltName; CRL checking is disabled; and HSTS is not enabled.
763 words, about 4 min4The Backup Tape That Carries Its Own Key
An insurer writes nightly database backups to LTO tapes using AES-256-GCM. Each backup job generates a fresh 256-bit key, but the key is written in plaintext in the tape header so that restore operators can decrypt without contacting another system.
766 words, about 4 min5Design Previews That Carry Hidden Payloads
A defense contractor's data-loss-prevention system blocks email attachments over 10 MB and scans documents for classification keywords. Investigators discover that an engineer has been uploading 2-4 MB PNG 'design previews' to a personal cloud account for eight months.
729 words, about 4 min