macOS Python Site-Packages .pth File Creation
Alerts on new .pth files created under macOS Python site-packages, a mechanism that can execute code at Python startup.
- Product
- macos
- Category
- file_event
- Author
- Andreas Braathen (mnemonic.io) (SigmaHQ), DRL 1.1
- Published
- 2024-04-25
- Updated
- 2026-07-31
ATT&CK techniques
ExecutionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags creation of Python path configuration files (.pth) under the macOS Python site-packages directory. .pth files can execute code during Python startup, enabling persistence or execution without the target module being explicitly imported by the initiating script. It relies on file creation telemetry capturing the target filename and matching it to the expected site-packages path and .pth extension.
Reporting behind it
- volexity.comhttps://www.volexity.com/blog/2024/04/12/zero-day-exploitation-of-unauthenticated-remote-code-execution-vulnerability-in-globalprotect-cve-2024-3400/
- virustotal.comhttps://www.virustotal.com/gui/file/3de2a4392b8715bad070b2ae12243f166ead37830f7c6d24e778985927f9caac
- docs.python.orghttps://docs.python.org/3/library/site.html
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules-threat-hunting/macos/file/file_event/file_event_macos_python_path_configuration_files.yml
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: macOS Python Site-Packages .pth File Creation
id: c310d9f5-f389-448d-9a5f-028968f0814a
related:
- id: e3652ba3-0ad8-4010-a957-b7ba369e7bac
type: similar
- id: fb96c26c-9f85-4ae7-af0d-ed1ed1f1f5ce
type: similar
- id: 4f394635-13ef-4599-b677-3353e0f84f55
type: derived
status: test
description: This rule flags creation of Python path configuration files (.pth) under the macOS Python site-packages directory. .pth files can execute code during Python startup, enabling persistence or execution without the target module being explicitly imported by the initiating script. It relies on file creation telemetry capturing the target filename and matching it to the expected site-packages path and .pth extension.
references:
- https://www.volexity.com/blog/2024/04/12/zero-day-exploitation-of-unauthenticated-remote-code-execution-vulnerability-in-globalprotect-cve-2024-3400/
- https://www.virustotal.com/gui/file/3de2a4392b8715bad070b2ae12243f166ead37830f7c6d24e778985927f9caac
- https://docs.python.org/3/library/site.html
- https://github.com/SigmaHQ/sigma/blob/master/rules-threat-hunting/macos/file/file_event/file_event_macos_python_path_configuration_files.yml
author: Andreas Braathen (mnemonic.io), Huntrule Team
date: 2024-04-25
tags:
- attack.execution
- attack.t1059.006
- detection.threat-hunting
logsource:
product: macos
category: file_event
detection:
selection:
TargetFilename|re: (?i)/lib/python3\.([5-9]|[0-9]{2})/site-packages/
TargetFilename|endswith: .pth
condition: selection
falsepositives:
- Although .pth files are discouraged due to potential security implications, these are legitimate files by specification.
level: medium
license: DRL-1.1