Detection rules › Sigma
Curl.EXE Execution With Custom UserAgent
Detects execution of curl.exe with custom useragent options
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control | T1071.001 Application Layer Protocol: Web Protocols |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
Rule body yaml
title: Curl.EXE Execution With Custom UserAgent
id: 3286d37a-00fd-41c2-a624-a672dcd34e60
status: test
description: Detects execution of curl.exe with custom useragent options
references:
- https://curl.se/docs/manpage.html
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1071.001/T1071.001.md#atomic-test-2---malicious-user-agents---cmd
author: frack113
date: 2022-01-23
modified: 2023-02-21
tags:
- attack.command-and-control
- attack.t1071.001
- detection.threat-hunting
logsource:
category: process_creation
product: windows
detection:
selection_curl:
- Image|endswith: '\curl.exe'
- Product: 'The curl executable'
selection_opt:
CommandLine|contains:
- ' -A '
- ' --user-agent '
condition: all of selection_*
falsepositives:
- Scripts created by developers and admins
- Administrative activity
level: medium
Stages and Predicates
Stage 0: condition
all of selection_*Stage 1: selection_curl
selection_curl:
- Image|endswith: '\curl.exe'
- Product: 'The curl executable'
Stage 2: selection_opt
selection_opt:
CommandLine|contains:
- ' -A '
- ' --user-agent '
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.
| Field | Kind | Values |
|---|---|---|
CommandLine | match |
|
Image | ends_with |
|
Product | eq |
|