Detection rules › Sigma
Renamed PAExec Execution
Detects execution of renamed version of PAExec. Often used by attackers
Known false positives
- Weird admins that rename their tools
- Software companies that bundle PAExec with their software and rename it, so that it is less embarrassing
- When executed with the "-s" flag. PAExec will copy itself to the "C:\Windows\" directory with a different name. Usually like this "PAExec-[XXXXX]-[ComputerName]"
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
Rule body
title: Renamed PAExec Execution
id: c4e49831-1496-40cf-8ce1-b53f942b02f9
related:
- id: 7b0666ad-3e38-4e3d-9bab-78b06de85f7b
type: obsolete
status: test
description: Detects execution of renamed version of PAExec. Often used by attackers
references:
- https://www.poweradmin.com/paexec/
- https://summit.fireeye.com/content/dam/fireeye-www/summit/cds-2018/presentations/cds18-technical-s05-att&cking-fin7.pdf
author: Florian Roth (Nextron Systems), Jason Lynch
date: 2021-05-22
modified: 2024-11-23
tags:
- attack.stealth
- attack.t1202
logsource:
category: process_creation
product: windows
detection:
selection:
- Description: 'PAExec Application'
- OriginalFileName: 'PAExec.exe'
- Product|contains: 'PAExec'
- Hashes|contains:
- IMPHASH=11D40A7B7876288F919AB819CC2D9802
- IMPHASH=6444f8a34e99b8f7d9647de66aabe516
- IMPHASH=dfd6aa3f7b2b1035b76b718f1ddc689f
- IMPHASH=1a6cca4d5460b1710a12dea39e4a592c
filter_main_known_location:
- Image|endswith: '\paexec.exe'
- Image|startswith: 'C:\Windows\PAExec-'
condition: selection and not 1 of filter_main_*
falsepositives:
- Weird admins that rename their tools
- Software companies that bundle PAExec with their software and rename it, so that it is less embarrassing
- When executed with the "-s" flag. PAExec will copy itself to the "C:\Windows\" directory with a different name. Usually like this "PAExec-[XXXXX]-[ComputerName]"
level: high
Stages and Predicates
Stage 0: condition
selection and not 1 of filter_main_*Stage 1: selection
selection:
- Description: 'PAExec Application'
- OriginalFileName: 'PAExec.exe'
- Product|contains: 'PAExec'
- Hashes|contains:
- IMPHASH=11D40A7B7876288F919AB819CC2D9802
- IMPHASH=6444f8a34e99b8f7d9647de66aabe516
- IMPHASH=dfd6aa3f7b2b1035b76b718f1ddc689f
- IMPHASH=1a6cca4d5460b1710a12dea39e4a592c
Stage 2: not filter_main_known_location
filter_main_known_location:
- Image|endswith: '\paexec.exe'
- Image|startswith: 'C:\Windows\PAExec-'
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
Image | ends_with | \paexec.exe | excludes:Image field:"Image" value:"\paexec.exe" |
Image | starts_with | C:\Windows\PAExec- | excludes:Image field:"Image" value:"C:\Windows\PAExec-" |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Description | eq |
| field:"Description" kind:eq value:"PAExec Application" |
Hashes | match |
| field:"Hashes" kind:match |
OriginalFileName | eq |
| field:"OriginalFileName" kind:eq value:"PAExec.exe" |
Product | match |
| field:"Product" kind:match value:"PAExec" |