Detection rules › Sigma

Potential Provlaunch.EXE Binary Proxy Execution Abuse

Status
test
Severity
medium
Log source
product windows, category process_creation
Author
Nasreddine Bencherchali (Nextron Systems), Swachchhanda Shrawan Poudel
Source
github.com/SigmaHQ/sigma

Detects child processes of "provlaunch.exe" which might indicate potential abuse to proxy execution.

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Potential Provlaunch.EXE Binary Proxy Execution Abuse
id: 7f5d1c9a-3e83-48df-95a7-2b98aae6c13c
related:
    - id: f9999590-1f94-4a34-a91e-951e47bedefd # CLI Abuse
      type: similar
    - id: 2a4b3e61-9d22-4e4a-b60f-6e8f0cde6f25 # CLI Registry
      type: similar
    - id: 7021255e-5db3-4946-a8b9-0ba7a4644a69 # Registry
      type: similar
status: test
description: Detects child processes of "provlaunch.exe" which might indicate potential abuse to proxy execution.
references:
    - https://lolbas-project.github.io/lolbas/Binaries/Provlaunch/
    - https://twitter.com/0gtweet/status/1674399582162153472
author: Nasreddine Bencherchali (Nextron Systems), Swachchhanda Shrawan Poudel
date: 2023-08-08
tags:
    - attack.stealth
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\provlaunch.exe'
    filter_main_covered_children:
        # Note: this filter is here to avoid duplicate alerting by f9999590-1f94-4a34-a91e-951e47bedefd
        - Image|endswith:
              - '\calc.exe'
              - '\cmd.exe'
              - '\cscript.exe'
              - '\mshta.exe'
              - '\notepad.exe'
              - '\powershell.exe'
              - '\pwsh.exe'
              - '\regsvr32.exe'
              - '\rundll32.exe'
              - '\wscript.exe'
        - Image|contains:
              - ':\PerfLogs\'
              - ':\Temp\'
              - ':\Users\Public\'
              - '\AppData\Temp\'
              - '\Windows\System32\Tasks\'
              - '\Windows\Tasks\'
              - '\Windows\Temp\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    ParentImage|endswith: '\provlaunch.exe'

Stage 2: not filter_main_covered_children

filter_main_covered_children:
    - Image|endswith:
          - '\calc.exe'
          - '\cmd.exe'
          - '\cscript.exe'
          - '\mshta.exe'
          - '\notepad.exe'
          - '\powershell.exe'
          - '\pwsh.exe'
          - '\regsvr32.exe'
          - '\rundll32.exe'
          - '\wscript.exe'
    - Image|contains:
          - ':\PerfLogs\'
          - ':\Temp\'
          - ':\Users\Public\'
          - '\AppData\Temp\'
          - '\Windows\System32\Tasks\'
          - '\Windows\Tasks\'
          - '\Windows\Temp\'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
Imageends_with\calc.exe
Imageends_with\cmd.exe
Imageends_with\cscript.exe
Imageends_with\mshta.exe
Imageends_with\notepad.exe
Imageends_with\powershell.exe
Imageends_with\pwsh.exe
Imageends_with\regsvr32.exe
Imageends_with\rundll32.exe
Imageends_with\wscript.exe
Imagematch:\PerfLogs\
Imagematch:\Temp\
Imagematch:\Users\Public\
Imagematch\AppData\Temp\
Imagematch\Windows\System32\Tasks\
Imagematch\Windows\Tasks\
Imagematch\Windows\Temp\

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
ParentImageends_with
  • \provlaunch.exe corpus 2 (sigma 2)