sigmamediumHunting

File Download Via Nscurl - MacOS

Detects the execution of the nscurl utility in order to download files.

MITRE ATT&CK

defense-evasioncommand-and-control

Detection Query

selection:
  Image|endswith: /nscurl
  CommandLine|contains:
    - "--download "
    - "--download-directory "
    - "--output "
    - "-dir "
    - "-dl "
    - -ld
    - "-o "
condition: selection

Author

Daniel Cortez

Created

2024-06-04

Data Sources

macosProcess Creation Events

Platforms

macos

References

Tags

attack.defense-evasionattack.command-and-controlattack.t1105

Raw Content

title: File Download Via Nscurl - MacOS
id: 6d8a7cf1-8085-423b-b87d-7e880faabbdf
status: test
description: Detects the execution of the nscurl utility in order to download files.
references:
    - https://www.loobins.io/binaries/nscurl/
    - https://www.agnosticdev.com/content/how-diagnose-app-transport-security-issues-using-nscurl-and-openssl
    - https://gist.github.com/nasbench/ca6ef95db04ae04ffd1e0b1ce709cadd
author: Daniel Cortez
date: 2024-06-04
tags:
    - attack.defense-evasion
    - attack.command-and-control
    - attack.t1105
logsource:
    category: process_creation
    product: macos
detection:
    selection:
        Image|endswith: '/nscurl'
        CommandLine|contains:
            - '--download '
            - '--download-directory '
            - '--output '
            - '-dir '
            - '-dl '
            - '-ld'
            - '-o '
    condition: selection
falsepositives:
    - Legitimate usage of nscurl by administrators and users.
level: medium