AN1399: Analytic 1399
Detects process injection by correlating memory manipulation API calls (e.g., VirtualAllocEx, WriteProcessMemory), suspicious thread creation (e.g., CreateRemoteThread), and unusual DLL loads within another process's context.
Analyst context for executives and security teams
AN1399 is a Windows detection analytic for identifying likely process injection by correlating signs of one process manipulating another process’s memory, creating suspicious threads, and loading unusual DLLs in another process context. For leaders, its value is in validating whether the SOC can see stealthy execution behavior that may bypass simple file- or command-line-based controls.
Executive priority
Prioritize this analytic as a coverage validation item for Windows endpoint resilience and incident response readiness. The business question is whether security teams can detect malicious code running inside otherwise legitimate processes, because that behavior can complicate triage, containment, and audit evidence. It is especially relevant when assessing endpoint telemetry quality, managed detection effectiveness, and control gaps beyond traditional malware blocking.
Technical view
SOC and detection engineering teams should validate whether Windows endpoint telemetry captures the API and behavioral chain described: memory manipulation calls such as VirtualAllocEx and WriteProcessMemory, suspicious remote thread creation such as CreateRemoteThread, and unusual DLL loads in another process’s context. Because no official detection logic or tactic mapping is supplied, teams should treat this as an analytic concept that requires local tuning, baselining, and correlation rather than a ready-to-deploy rule.
Likely telemetry
- Windows endpoint detection and response telemetry
- Process creation and parent-child process context
- Cross-process memory manipulation events or API-call telemetry
- Remote thread creation telemetry
- DLL/module load events
Detection direction
- Validate that telemetry can correlate memory allocation or write activity into another process with subsequent thread creation or DLL loading.
- Tune against known legitimate software that performs cross-process memory operations, such as security tools, management agents, debuggers, or application compatibility components.
- Prioritize detections where the source process, target process, DLL path, signer, or execution context is unusual for the environment.
- Confirm that alert evidence supports incident response decisions, including source process, target process, loaded module, user context, and host details.
- Document blind spots where API-level, remote-thread, or module-load telemetry is unavailable on Windows endpoints.
Mitigation priorities
- First, ensure endpoint telemetry collection is sufficient for cross-process memory, thread, and DLL-load visibility.
- Baseline legitimate cross-process activity to reduce false positives before high-severity alerting.
- Use endpoint hardening and application control approaches where appropriate to reduce unauthorized code execution paths.
- Integrate the analytic into incident response playbooks so analysts know how to collect process, module, and memory-related evidence.
- Review managed detection or SOC service coverage against this behavior rather than assuming file-based detections are enough.
Analyst notes and limits
The supplied object is a detection analytic, not a technique object. Its main decision value is coverage assessment for Windows process-injection-like behavior. Relationship context, tactic mapping, and official detection logic were not supplied, so local implementation should be evidence-driven.
Only the official description, platform, external reference, and object metadata were supplied. No relationships, tactic mappings, detection pseudocode, data source list, mitigations, or procedure examples were provided. This take does not infer attribution, active exploitation, impact, or guaranteed detectability.
Analytic 1399
Detects process injection by correlating memory manipulation API calls (e.g., VirtualAllocEx, WriteProcessMemory), suspicious thread creation (e.g., CreateRemoteThread), and unusual DLL loads within another process's context.
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
All related ATT&CK context
No relationships are available in the current normalized data for this object.
Object version and sync metadata
The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates .
Imported snapshots across ATT&CK releases (1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.0 | Current bundle | 9bd69749f8e9… |
Mirrored ATT&CK source object
The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
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mitre-attack AN1399Open source URL
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