Detection rules › Sigma

Insecure Transfer Via Curl.EXE

Status
test
Severity
medium
Log source
category process_creation, product windows
Author
X__Junior (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects execution of "curl.exe" with the "--insecure" flag.

Known false positives

  • Access to badly maintained internal or development systems

MITRE ATT&CK coverage

TacticTechniques
ExecutionNo specific technique

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: Insecure Transfer Via Curl.EXE
id: cb9cc1d1-e84e-4bdc-b7ad-c31b1b7908ec
status: test
description: Detects execution of "curl.exe" with the "--insecure" flag.
references:
    - https://curl.se/docs/manpage.html
author: X__Junior (Nextron Systems)
date: 2023-06-30
tags:
    - attack.execution
logsource:
    product: windows
    category: process_creation
detection:
    selection_img:
        - Image|endswith: '\curl.exe'
        - OriginalFileName: 'curl.exe'
    selection_cli:
        - CommandLine|re: '\s-k\s'
        - CommandLine|contains: '--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_connection/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|re: '\s-k\s'
    - CommandLine|contains: '--insecure'

Indicators

These rows show field, operator, and value matches.