March 10, 20262 min read
Building an Advanced Framework Against Ransomware
A layered defense model for ransomware resilience, from prevention and detection through containment and recovery — grounded in NIST CSF and MITRE ATT&CK.
Ransomware defense fails most often not because a single control was missing, but because controls weren't layered. A single strong perimeter firewall, a single EDR agent, or a single backup job is a point of failure, not a defense.
The Layered Model
The framework maps directly onto the five NIST CSF functions — Identify, Protect, Detect, Respond, Recover — with MITRE ATT&CK tactics used to validate coverage at each layer.
1. Identify
- Asset inventory tied to business criticality, not just IP address
- Attack surface mapping: exposed RDP, VPN endpoints, unpatched CVEs
- Third-party and supply-chain risk scoring
2. Protect
- Least-privilege Active Directory tiering (Tier 0/1/2 separation)
- Application allowlisting on servers handling sensitive data
- Immutable, offline (3-2-1-1) backup architecture — the single highest-leverage control against ransomware specifically, since it removes the extortion incentive entirely
3. Detect
- Behavioral EDR tuned for mass file-modification and shadow-copy deletion
(
vssadmin delete shadowsis still one of the highest-signal indicators) - Canary files distributed across file shares
- Threat intel feeds mapped to known ransomware affiliate TTPs
4. Respond
- Pre-authorized network isolation runbooks (segment before you investigate)
- Clear internal/external communication chain, tested via tabletop exercises
- Chain-of-custody procedures for forensic evidence
5. Recover
- Recovery time objectives (RTO) validated quarterly via live restore drills, not just backup completion checks
- Rebuild-from-known-good, never restore-in-place onto a potentially reinfected host
The Real Failure Mode
In practice, the compromises I've seen trace back to identity, not malware: a stale service account with domain admin rights, or MFA that covered VPN but not the RDP jump box behind it. Ransomware is the payload — the actual failure is almost always a gap in Protect or Detect that existed long before the encryption event.
Treat ransomware readiness as an identity and backup-integrity problem first, and a malware-signature problem a distant second.