Indicator Removal: Clear Windows Event Logs T1070.001
Tactic: Stealth
Adversaries may clear Windows Event Logs to hide the activity of an intrusion. Windows Event Logs are a record of a computer's alerts and notifications. There are three system-defined sources of events: System, Application, and Security, with five event types: Error, Warning, Information, Success Audit, and Failure Audit.
Events covered
8 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| Security-Auditing | Event ID 4719 | System audit policy was changed. |
| Eventlog | Event ID 104 | The LogFileCleared.Channel log file was cleared. |
| Eventlog | Event ID 1102 | The audit log was cleared. |
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
| PowerShell | Event ID 800 | Event ID 800 |
Authoring guide
Patterns shared across the 14 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 (25 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 (79 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 (3 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 5 rules
- Event log clear attempt (command)
- Event log clear attempt (PowerShell)
- Event log clear attempt (wmi)
- Event log cleared (native)
- Event log cleared using Diagnostics (via PowerShell)
Elastic 5 rules
- Clearing Windows Event Logs
- Disable Windows Event and Security Logs Using Built-in Tools
- PowerShell Script with Log Clear Capabilities
- Sensitive Audit Policy Sub-Category Disabled
- Windows Event Logs Cleared
Splunk 2 rules
- Cisco IOS XE Log Clearing Sequence With Optional Loopback Removal
- Clear Windows Event Logs (Windows Event Log)