HackTool - SharpImpersonation Execution

Status: test
Severity: high
Log source: category process_creation, product windows
Author: Sai Prashanth Pulisetti @pulisettis, Nasreddine Bencherchali (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects execution of the SharpImpersonation tool. Which can be used to manipulate tokens on a Windows computers remotely (PsExec/WmiExec) or interactively

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1134.001` Access Token Manipulation: Token Impersonation/Theft `T1134.003` Access Token Manipulation: Make and Impersonate Token
Stealth	`T1134.001` Access Token Manipulation: Token Impersonation/Theft `T1134.003` Access Token Manipulation: Make and Impersonate Token

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: HackTool - SharpImpersonation Execution
id: f89b08d0-77ad-4728-817b-9b16c5a69c7a
related:
    - id: cf0c254b-22f1-4b2b-8221-e137b3c0af94
      type: similar
status: test
description: Detects execution of the SharpImpersonation tool. Which can be used to manipulate tokens on a Windows computers remotely (PsExec/WmiExec) or interactively
references:
    - https://s3cur3th1ssh1t.github.io/SharpImpersonation-Introduction/
    - https://github.com/S3cur3Th1sSh1t/SharpImpersonation
author: Sai Prashanth Pulisetti @pulisettis, Nasreddine Bencherchali (Nextron Systems)
date: 2022-12-27
modified: 2023-02-13
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1134.001
    - attack.t1134.003
logsource:
    product: windows
    category: process_creation
detection:
    selection_img:
        - Image|endswith: '\SharpImpersonation.exe'
        - OriginalFileName: 'SharpImpersonation.exe'
    selection_cli:
        - CommandLine|contains|all:
              - ' user:'
              - ' binary:'
        - CommandLine|contains|all:
              - ' user:'
              - ' shellcode:'
        - CommandLine|contains:
              - ' technique:CreateProcessAsUserW'
              - ' technique:ImpersonateLoggedOnuser'
    condition: 1 of selection_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

1 of selection_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith: '\SharpImpersonation.exe'
    - OriginalFileName: 'SharpImpersonation.exe'

Stage 2: `selection_cli`

selection_cli:
    - CommandLine|contains|all:
          - ' user:'
          - ' binary:'
    - CommandLine|contains|all:
          - ' user:'
          - ' shellcode:'
    - CommandLine|contains:
          - ' technique:CreateProcessAsUserW'
          - ' technique:ImpersonateLoggedOnuser'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`binary:` `shellcode:` `technique:CreateProcessAsUserW` `technique:ImpersonateLoggedOnuser` `user:`	`field:"CommandLine" kind:match`
`Image`	ends_with	`\SharpImpersonation.exe`	`field:"Image" kind:ends_with value:"\SharpImpersonation.exe"`
`OriginalFileName`	eq	`SharpImpersonation.exe`	`field:"OriginalFileName" kind:eq value:"SharpImpersonation.exe"`