securityskills Malware Triage
Analyze suspicious samples safely and extract actionable indicators fast.
Safety First
- Isolated VM or dedicated sandbox (Cuckoo/ANY.RUN/vendor sandbox), network simulated or sinkholed
- Samples stored in password-protected archives, hash-named; never opened on analysis-adjacent hosts
- Work from snapshots; revert after every detonation
1. Static Triage
- Hashes (MD5/SHA256), file type, entropy (
file,pestudio-style overview) - Strings: URLs, mutexes, registry paths, PDB paths, C2 patterns
- PE specifics: imports of interest (network, process injection, crypto APIs), digital signature validity, packer detection (entropy + section names)
- Document metadata (Office macros, embedded objects, remote templates)
2. Dynamic Detonation
- Execute in sandbox with monitoring: file, registry, network, process activity
- Capture: dropped files, persistence mechanism, C2 beacons (domains/IPs with ports/protocols)
- Trigger-dependent malware: require user interaction simulation, geo/fate checks, or debugger awareness — escalate to debugging if silent
3. Behavior Extraction
- Persistence: Run keys, services, scheduled tasks, WMI subscriptions
- Injection: process hollowing, APC, SetWindowsHookEx targets
- Exfiltration: DNS tunneling patterns, HTTP POST shapes, known protocol beacons
- Defense evasion: AV service stops, AMSI/ETW patching, timestamp manipulation
4. Classification and Reporting
- Family attribution via YARA rules against sample set; note confidence
- Map observed behavior to ATT&CK techniques
- Produce: IOCs (machine-readable, STIX if required), detection guidance (YARA + behavioral), and a one-page triage summary
Escalation Criteria
Deep-dive reversing (IDA/Ghidra) only when: C2 protocol reconstruction, config extraction, or unpacking is required for detection/response — not for curiosity.