Detection rules › Sigma
Wget Creating Files in Tmp Directory
Detects the use of wget to download content in a temporary directory such as "/tmp" or "/var/tmp"
Known false positives
- Legitimate downloads of files in the tmp folder.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control |
Telemetry coverage
| Platform | Record / event type |
|---|---|
| Linux | Event ID 11: File created |
Rule body
title: Wget Creating Files in Tmp Directory
id: 35a05c60-9012-49b6-a11f-6bab741c9f74
status: test
description: Detects the use of wget to download content in a temporary directory such as "/tmp" or "/var/tmp"
references:
- https://blogs.jpcert.or.jp/en/2023/05/gobrat.html
- https://jstnk9.github.io/jstnk9/research/GobRAT-Malware/
- https://www.virustotal.com/gui/file/60bcd645450e4c846238cf0e7226dc40c84c96eba99f6b2cffcd0ab4a391c8b3/detection
- https://www.virustotal.com/gui/file/3e44c807a25a56f4068b5b8186eee5002eed6f26d665a8b791c472ad154585d1/detection
author: Joseliyo Sanchez, @Joseliyo_Jstnk
date: 2023-06-02
tags:
- attack.command-and-control
- attack.t1105
logsource:
product: linux
category: file_event
detection:
selection:
Image|endswith: '/wget'
TargetFilename|startswith:
- '/tmp/'
- '/var/tmp/'
condition: selection
falsepositives:
- Legitimate downloads of files in the tmp folder.
level: medium
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
Image|endswith: '/wget'
TargetFilename|startswith:
- '/tmp/'
- '/var/tmp/'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Image | ends_with |
| field:"Image" kind:ends_with value:"/wget" |
TargetFilename | starts_with |
| field:"TargetFilename" kind:starts_with |