Attack Ent T1027 007 Dynamic API Resolution

MITRE ATT&CK T1027.007: Dynamic API Resolution

When to use this skill

Use this skill when the task involves T1027.007, Dynamic API Resolution, enterprise ATT&CK, TTP mapping, detection engineering, hunting, incident-response enrichment, control validation, or authorized adversary-emulation planning. Treat it as a defensive analysis aid: keep outputs focused on understanding, detecting, mitigating, and safely validating this ATT&CK sub-technique.

Technique context

• ATT&CK domain: enterprise
• ATT&CK ID: T1027.007
• Technique name: Dynamic API Resolution
• Type: sub-technique
• ATT&CK URL: https://attack.mitre.org/techniques/T1027/007
• Tactics: stealth
• Platforms: Windows
• Required permissions: Not specified
• Effective permissions: Not specified
• Defenses bypassed: Not specified

ATT&CK description

Adversaries may obfuscate then dynamically resolve API functions called by their malware in order to conceal malicious functionalities and impair defensive analysis. Malware commonly uses various Native API functions provided by the OS to perform various tasks such as those involving processes, files, and other system artifacts.

API functions called by malware may leave static artifacts such as strings in payload files. Defensive analysts may also uncover which functions a binary file may execute via an import address table (IAT) or other structures that help dynamically link calling code to the shared modules that provide functions.(Citation: Huntress API Hash)(Citation: IRED API Hashing)

To avoid static or other defensive analysis, adversaries may use dynamic API resolution to conceal malware characteristics and functionalities. Similar to Software Packing, dynamic API resolution may change file signatures and obfuscate malicious API function calls until they are resolved and invoked during runtime.

Various methods may be used to obfuscate malware calls to API functions. For example, hashes of function names are commonly stored in malware in lieu of literal strings. Malware can use these hashes (or other identifiers) to manually reproduce the linking and loading process using functions such as GetProcAddress() and LoadLibrary(). These hashes/identifiers can also be further obfuscated using encryption or other string manipulation tricks (requiring various forms of Deobfuscate/Decode Files or Information during execution).(Citation: BlackHat API Packers)(Citation: Drakonia HInvoke)(Citation: Huntress API Hash)

Agent workflow

1. Clarify scope: identify the system, asset class, log sources, cloud or endpoint platform, and whether the user wants triage, detection, coverage assessment, or safe emulation planning.
2. Load bundled resources as needed: use references/technique-profile.json for structured metadata, references/detection-and-mitigation.md for triage and telemetry guidance, references/known-threat-context.md for ATT&CK relationship context, and templates/ for repeatable outputs.
3. Map observations to ATT&CK: compare the user's evidence to the ATT&CK description, tactics, platforms, and known procedure patterns before asserting a match.
4. Produce defensive outputs: prioritize hypotheses, telemetry requirements, detection logic ideas, validation steps, containment guidance, and mitigations.
5. Preserve uncertainty: distinguish confirmed evidence, plausible indicators, assumptions, and gaps. Recommend what to collect next.
6. Stay safe: do not provide malware, credential theft, persistence, evasion, destructive automation, or unauthorized exploitation instructions. For adversary emulation, keep steps bounded to approved lab or control-validation contexts and omit operational abuse details.

Bundled resources

• references/technique-profile.json: machine-readable ATT&CK metadata for this technique.
• references/detection-and-mitigation.md: detection notes, telemetry checklist, triage questions, mitigation candidates, and false-positive considerations.
• references/known-threat-context.md: ATT&CK relationship context with attribution cautions.
• templates/detection-brief.md: detection engineering brief template.
• templates/hunt-plan.md: threat hunt plan template.
• templates/incident-response-note.md: incident response note template.
• templates/coverage-assessment.md: ATT&CK coverage assessment template.
• scripts/render_brief.py: local helper that renders a Markdown defensive brief from technique-profile.json.
• assets/output-schema.json: JSON schema for structured technique analysis outputs.

To generate a quick brief, run python scripts/render_brief.py --output brief.md from inside this skill directory, or adapt the templates directly.

Detection guidance

No ATT&CK detection guidance was present in the source STIX object.

Useful telemetry and data sources

• Not specified in the STIX object.

Mitigations to consider

• No ATT&CK mitigation relationships were present in the source STIX bundle.

Known threat context

Use these examples only as contextual leads, not as proof that an observed event is this technique:

• AvosLocker (malware)
• Bazar (malware)
• Brute Ratel C4 (tool)
• CANONSTAGER (malware)
• CHIMNEYSWEEP (malware)
• CLAIMLOADER (malware)
• HTTPTroy (malware)
• HiddenFace (malware)
• Kimsuky (intrusion-set)
• LODEINFO (malware)
• LP-Notes (malware)
• Latrodectus (malware)
• Lazarus Group (intrusion-set)
• Mustang Panda (intrusion-set)
• PlugX (malware)
• Pteranodon (malware)
• Raccoon Stealer (malware)
• Samurai (malware)
• SplatDropper (malware)
• TONESHELL (malware)

Recommended output pattern

When responding with this skill, structure the answer as:

• Assessment: whether the evidence supports this ATT&CK mapping and why.
• Evidence: specific indicators, logs, behaviors, and assumptions.
• Detection: telemetry sources, analytic logic, and tuning considerations.
• Response: containment, eradication, recovery, and validation actions.
• Coverage gaps: missing logs, sensors, controls, or environmental details.
• References: include the ATT&CK URL and any user-provided evidence references.