How should security teams detect process hollowing and process herpaderping in Windows environments?

Security teams should enable Sysmon v13 process tampering monitoring and make sure Event ID 25 is being collected and forwarded into central monitoring. The key is to treat these techniques as process masquerading events, not just malware signatures. Pair host telemetry with SIEM alerting so suspicious in memory execution under trusted process names is surfaced quickly for investigation and containment.

How to spot process hollowing and herpaderping in Windows telemetry

Detection starts with treating these as process tampering and masquerading problems, not generic malware names. The most useful host signal is process-creation and tampering telemetry that lets you compare what was on disk, what was launched, and what later executed in memory. When those three views disagree, the process deserves investigation.

For Windows defenders, that means watching for a legitimate process image that later behaves like a different binary, or for a process whose memory, parentage, command line, and on-disk content do not line up. MITRE ATT&CK Enterprise Matrix is a useful reference point for mapping those behaviours to broader credential-access and defence-evasion patterns, while NIST Cybersecurity Framework 2.0 helps teams organise detection and response around identify, detect, and respond functions.

The practical indicator set is broader than a single event ID. Look for trusted Windows or signed binaries that suddenly spawn unusual child processes, load unexpected modules, or execute code regions inconsistent with the original image. If the process name looks normal but the memory layout, file metadata, or command-line context is not, the event should be treated as suspicious until proven otherwise.

What telemetry matters most for hollowing and herpaderping

Sysmon process tampering events are the best first-line host control because they can surface the kind of post-launch manipulation that signature-only tools miss. Event ID 25 is especially valuable when it is collected consistently and forwarded to central monitoring, because it gives analysts a direct hook for tampering-focused triage rather than forcing them to infer manipulation from later symptoms.

Use that telemetry alongside process creation, image load, network, and script telemetry so you can reconstruct the sequence. The important question is whether the process executed code that no longer matches the original file, or whether the file was overwritten after launch to disguise what ran. SANS Security Resources is a useful practitioner destination for detection engineering and SOC workflow patterns, and NIST SP 800-53 Rev 5 Security and Privacy Controls provides a control lens for audit logging, monitoring, and system integrity.

Correlate suspicious process events with indicators such as unusual parent-child relationships, unsigned or newly dropped binaries, memory-backed execution, and activity that occurs shortly after the file appears on disk. Those combinations are more important than any single artefact, because process hollowing and herpaderping are both designed to make one view of the process look benign while another view is malicious.

How analysts should triage suspected masquerading events

When a detection fires, the next step is to preserve the relationship between the process image, its memory state, and the surrounding host artefacts. In practice, that means checking the original file path, hash, signer, parent process, command line, loaded modules, and any post-launch file modifications before containment changes overwrite the evidence.

A strong triage decision rule is simple: if the process can be trusted by name but not by provenance, isolate first and explain later. If the process is running from a path that should be static but its on-disk content changed after launch, or if the in-memory behaviour does not match the supposed binary, the event should be escalated as likely masquerading rather than routine malware noise. NIST Cybersecurity Framework 2.0 is helpful here because it reinforces the detect-to-respond handoff, while MITRE ATT&CK Enterprise Matrix helps analysts place the activity in the wider attack chain.

Risk and Threat Considerations

These techniques are risky because they abuse the gap between what defenders see on disk and what the CPU actually executes. That lets attackers hide inside trusted process names, defeat naive allowlisting, and blend into normal Windows activity long enough to steal credentials, stage payloads, or move laterally.

Failure mechanism: defenders rely on filename, signer, or static hash alone, while the attacker replaces or hollows the process after launch so the memory image and the file image no longer match.

Impact: malicious code can run under trusted process context, which raises the chance of missed detection, delayed containment, and secondary compromise across adjacent systems.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

MITRE ATT&CK addresses the attack and risk surface, while NIST CSF 2.0 and NIST SP 800-53 Rev 5 set the governance and control requirements practitioners need to meet.

Framework	Control / Reference	Relevance
MITRE ATT&CK	T1036 — Masquerading	Process hollowing and herpaderping rely on process masquerading and trust abuse.
Recommendation — Map tampering signals to masquerading and hunt for renamed or substituted execution paths.
NIST CSF 2.0	DE.CM-01 — Networks and network services are monitored to detect potential cybersecurity events	Windows tampering detection depends on continuous monitoring and alerting for suspicious execution.
	DE.AE-02 — Anomalous cybersecurity events are detected	Process hollowing and herpaderping are anomalous execution behaviours needing detection logic.
Recommendation — Monitor host telemetry continuously and alert on suspicious process tampering patterns. Tune detections to flag abnormal process behaviour, not only known malware signatures.
NIST SP 800-53 Rev 5	AU-6 — Audit Record Review, Analysis, and Reporting	Sysmon Event ID 25 only helps when audit records are reviewed and correlated in central monitoring.
	SI-4 — System Monitoring	Host monitoring is the core control for identifying process hollowing and herpaderping.
	CM-8 — System Component Inventory	Trusted process masquerading is easier to spot when normal binaries and their roles are inventoried.
Recommendation — Review and correlate tampering audit records in the SIEM for suspicious execution. Deploy system monitoring that detects tampering, memory execution, and process anomalies. Maintain a known-good inventory of expected binaries and process roles for comparison.

Practitioner Guidance

What to prioritise: Make Sysmon process tampering telemetry, especially Event ID 25, part of your standard Windows detection baseline, and ensure it reaches the SIEM with enough surrounding process context to support triage.

What to verify: Confirm that your detections can compare process lineage, file state, and in-memory behaviour, because a hollowed or herpaderped process is often only obvious when those three views are analysed together.

What good looks like: Analysts can rapidly distinguish benign process anomalies from true masquerading events, and suspicious trusted-process execution is escalated before the attacker can use it for persistence or lateral movement.

Practitioner takeaway: Detection succeeds here when telemetry is built to expose mismatch, not just malware, so the control objective is to surface provenance breaks quickly enough that trusted-looking code cannot hide long enough to matter.