huntrule

Windows Process Creation: SDelete Used for File Overwrite

Alerts when sdelete.exe runs in a way consistent with file overwrite to impede forensic recovery.

FreeUnreviewedSigmahighv1
title: "Windows Process Creation: SDelete Used for File Overwrite"
id: 15ab72f0-1af7-4d67-9c92-70ac567ee718
status: test
description: This rule flags Windows process executions where the binary name is sdelete.exe and the command line does not match patterns associated with alternate behavior (e.g., specific flags like -h, -c, -z, or the help switch). SDelete can be used to overwrite file contents rather than just free space, which can reduce forensic artifacts and hinder incident response. The detection relies on process creation telemetry, specifically the executable filename and command-line arguments.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1485/T1485.md
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_sysinternals_sdelete.yml
author: frack113, Huntrule Team
date: 2021-06-03
modified: 2023-02-28
tags:
  - attack.impact
  - attack.t1485
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    OriginalFileName: sdelete.exe
  filter:
    CommandLine|contains:
      - " -h"
      - " -c"
      - " -z"
      - " /\\?"
  condition: selection and not filter
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: a4824fca-976f-4964-b334-0621379e84c4
    type: derived

What it detects

This rule flags Windows process executions where the binary name is sdelete.exe and the command line does not match patterns associated with alternate behavior (e.g., specific flags like -h, -c, -z, or the help switch). SDelete can be used to overwrite file contents rather than just free space, which can reduce forensic artifacts and hinder incident response. The detection relies on process creation telemetry, specifically the executable filename and command-line arguments.

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.