PowerShell timestomping via file timestamp property and setter usage (Windows)
Identifies PowerShell timestomping attempts by matching script text that sets file creation, access, and write timestamps.
- Product
- windows
- Category
- ps_script
- Author
- frack113 (SigmaHQ), DRL 1.1
- Published
- 2021-08-03
- Updated
- 2026-07-31
ATT&CK techniques
Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags PowerShell script content that sets or assigns file timestamp properties and uses .NET methods to change file creation, last access, and last write times. Attackers may timestomp files to obscure activity by making timestamps appear consistent with existing files or normal activity. The detection relies on PowerShell Script Block Logging telemetry matching specific timestamp property and setter expressions.
Reporting behind it
- github.comhttps://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1070.006/T1070.006.md
- offensive-security.comhttps://www.offensive-security.com/metasploit-unleashed/timestomp/
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_timestomp.yml
Changelog
v2- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: PowerShell timestomping via file timestamp property and setter usage (Windows)
id: a0f7a1d4-e82b-4b75-86e7-d2dc12fe8754
status: test
description: This rule flags PowerShell script content that sets or assigns file timestamp properties and uses .NET methods to change file creation, last access, and last write times. Attackers may timestomp files to obscure activity by making timestamps appear consistent with existing files or normal activity. The detection relies on PowerShell Script Block Logging telemetry matching specific timestamp property and setter expressions.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1070.006/T1070.006.md
- https://www.offensive-security.com/metasploit-unleashed/timestomp/
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/powershell/powershell_script/posh_ps_timestomp.yml
author: frack113, Huntrule Team
date: 2021-08-03
modified: 2022-12-25
tags:
- attack.stealth
- attack.t1070.006
logsource:
product: windows
category: ps_script
definition: "Requirements: Script Block Logging must be enabled"
detection:
selection_ioc:
ScriptBlockText|contains:
- .CreationTime =
- .LastWriteTime =
- .LastAccessTime =
- "[IO.File]::SetCreationTime"
- "[IO.File]::SetLastAccessTime"
- "[IO.File]::SetLastWriteTime"
condition: selection_ioc
falsepositives:
- Legitimate admin script
level: medium
license: DRL-1.1
related:
- id: c6438007-e081-42ce-9483-b067fbef33c3
type: derived