Event Triggered Execution: Component Object Model Hijacking T1546.015
Tactics: Privilege Escalation, Persistence
Adversaries may establish persistence by executing malicious content triggered by hijacked references to Component Object Model (COM) objects. COM is a system within Windows to enable interaction between software components through the operating system. References to various COM objects are stored in the Registry.
Events covered
9 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Sysmon | Event ID 12 | RegistryEvent (Object create and delete) |
| Sysmon | Event ID 13 | RegistryEvent (Value Set) |
| Sysmon | Event ID 14 | RegistryEvent (Key and Value Rename) |
| Security-Auditing | Event ID 4657 | A registry value was modified. |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| Defender-DeviceRegistryEvents | RegistryValueSet | Registry value set |
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Authoring guide
Patterns shared across the 22 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.
Fields filtered most (17 distinct)
The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.
Top indicator values (110 distinct)
Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.
Exclusions (66 distinct)
Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.
Rules under this technique
Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.
Sigma 9 rules
- COM Hijacking via TreatAs
- COM Object Hijacking Via Modification Of Default System CLSID Default Value
- Potential COM Object Hijacking Via TreatAs Subkey - Registry
- Potential Persistence Using DebugPath
- Potential Persistence Via Scrobj.dll COM Hijacking
- Potential PSFactoryBuffer COM Hijacking
- Rundll32 Registered COM Objects
- SOURGUM Actor Behaviours
- Suspicious GetTypeFromCLSID ShellExecute
Elastic 2 rules
Splunk 10 rules
- Powershell COM Hijacking InprocServer32 Modification
- Powershell Execute COM Object
- Rundll32 Spawned by Disk Cleanup (Sysmon)
- Rundll32 Spawned by Disk Cleanup (Windows Event Log)
- Suspicious DLLhost Execution (EDR)
- Suspicious DLLhost Execution (PowerShell)
- Suspicious DLLhost Execution (Windows Event Log)
- Suspicious InprocServer32 Registry Modification (Sysmon)
- Suspicious InprocServer32 Registry Modification (Windows Event Log)
- Windows COM Hijacking InprocServer32 Modification