Detection rules › Sigma

Unsigned .node File Loaded

Status
experimental
Severity
medium
Log source
category image_load, product windows
Author
Jonathan Beierle (@hullabrian)
Source
github.com/SigmaHQ/sigma

Detects the loading of unsigned .node files. Adversaries may abuse a lack of .node integrity checking to execute arbitrary code inside of trusted applications such as Slack. .node files are native add-ons for Electron-based applications, which are commonly used for desktop applications like Slack, Discord, and Visual Studio Code. This technique has been observed in the DripLoader malware, which uses unsigned .node files to load malicious native code into Electron applications.

Known false positives

  • VsCode extensions or similar legitimate tools might use unsigned .node files. These should be investigated on a case-by-case basis, and whitelisted if determined to be benign.

MITRE ATT&CK coverage

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 7: Image loaded

Rule body

title: Unsigned .node File Loaded
id: e5f5c693-52d7-4de5-88ae-afbfbce85595
status: experimental
description: |
    Detects the loading of unsigned .node files.
    Adversaries may abuse a lack of .node integrity checking to execute arbitrary code inside of trusted applications such as Slack.
    .node files are native add-ons for Electron-based applications, which are commonly used for desktop applications like Slack, Discord, and Visual Studio Code.
    This technique has been observed in the DripLoader malware, which uses unsigned .node files to load malicious native code into Electron applications.
references:
    - https://www.coreycburton.com/blog/driploader-case-study
    - https://github.com/CoreyCBurton/DripLoaderNG
    - https://www.electronjs.org/docs/latest/tutorial/native-code-and-electron
author: Jonathan Beierle (@hullabrian)
date: 2025-11-22
tags:
    - attack.execution
    - attack.privilege-escalation
    - attack.persistence
    - attack.stealth
    - attack.t1129
    - attack.t1574.001
    - attack.t1036.005
logsource:
    category: image_load
    product: windows
detection:
    selection_node_extension:
        ImageLoaded|endswith: '.node'
    selection_status:
        - Signed: 'false'
        - SignatureStatus: 'Unavailable'
    filter_optional_vscode_jupyter:
        Image|endswith: '\Code.exe'
        ImageLoaded|contains: '.vscode\extensions\ms-toolsai.jupyter-'
        ImageLoaded|endswith:
            - '\electron.napi.node'
            - '\node.napi.glibc.node'
    condition: all of selection_* and not 1 of filter_optional_*
falsepositives:
    - VsCode extensions or similar legitimate tools might use unsigned .node files. These should be investigated on a case-by-case basis, and whitelisted if determined to be benign.
level: medium

Stages and Predicates

Stage 0: condition

all of selection_* and not 1 of filter_optional_*

Stage 1: selection_node_extension

selection_node_extension:
    ImageLoaded|endswith: '.node'

Stage 2: selection_status

selection_status:
    - Signed: 'false'
    - SignatureStatus: 'Unavailable'

Stage 3: not filter_optional_vscode_jupyter

filter_optional_vscode_jupyter:
    Image|endswith: '\Code.exe'
    ImageLoaded|contains: '.vscode\extensions\ms-toolsai.jupyter-'
    ImageLoaded|endswith:
        - '\electron.napi.node'
        - '\node.napi.glibc.node'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
ImageLoadedends_with\electron.napi.nodeexcludes:ImageLoaded field:"ImageLoaded" value:"\electron.napi.node"
ImageLoadedends_with\node.napi.glibc.nodeexcludes:ImageLoaded field:"ImageLoaded" value:"\node.napi.glibc.node"
Imageends_with\Code.exeexcludes:Image field:"Image" value:"\Code.exe"
ImageLoadedmatch.vscode\extensions\ms-toolsai.jupyter-excludes:ImageLoaded field:"ImageLoaded" value:".vscode\extensions\ms-toolsai.jupyter-"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ImageLoadedends_with
  • .node
field:"ImageLoaded" kind:ends_with value:".node"
SignatureStatuseq
  • Unavailable corpus 2 (sigma 1, splunk 1)
field:"SignatureStatus" kind:eq value:"Unavailable"
Signedeq
  • false corpus 9 (splunk 5, sigma 4)
field:"Signed" kind:eq value:"false"