Detection rules › Sigma
Insecure Proxy/DOH Transfer Via Curl.EXE
Detects execution of "curl.exe" with the "insecure" flag over proxy or DOH.
Known false positives
- Access to badly maintained internal or development systems
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | No specific technique |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
Rule body
title: Insecure Proxy/DOH Transfer Via Curl.EXE
id: 2c1486f5-02e8-4f86-9099-b97f2da4ed77
status: test
description: Detects execution of "curl.exe" with the "insecure" flag over proxy or DOH.
references:
- https://curl.se/docs/manpage.html
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-07-27
tags:
- attack.execution
logsource:
product: windows
category: process_creation
detection:
selection_img:
- Image|endswith: '\curl.exe'
- OriginalFileName: 'curl.exe'
selection_cli:
CommandLine|contains:
- '--doh-insecure'
- '--proxy-insecure'
condition: all of selection_*
falsepositives:
- Access to badly maintained internal or development systems
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_curl_insecure_proxy_or_doh/info.yml
Stages and Predicates
Stage 0: condition
all of selection_*Stage 1: selection_img
selection_img:
- Image|endswith: '\curl.exe'
- OriginalFileName: 'curl.exe'
Stage 2: selection_cli
selection_cli:
CommandLine|contains:
- '--doh-insecure'
- '--proxy-insecure'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match |
Image | ends_with |
| field:"Image" kind:ends_with value:"\curl.exe" |
OriginalFileName | eq |
| field:"OriginalFileName" kind:eq value:"curl.exe" |