Detection rules › Splunk

Shai-Hulud 2 Exfiltration Artifact Files

Status
production
Severity
medium
Group by
CreationUtcTime, computer_name, event_action, file_access_time, file_acl, file_hash, file_modify_time, file_name, file_size, process_guid, process_id, target_filename, user, vendor_product
Author
Michael Haag, Splunk
Source
github.com/splunk/security_content

Detects creation of exfiltration artifact files associated with Shai-Hulud 2.0 npm supply chain malware. The malware creates cloud.json, contents.json, environment.json, truffleSecrets.json, and actionsSecrets.json files containing harvested credentials from AWS, Azure, GCP, GitHub secrets, and environment variables. These files are staged before being pushed to attacker-controlled repositories.

Known false positives

  • Low but possible. Generic filenames like cloud.json or environment.json may appear in legitimate contexts. Correlate with npm install activity or suspicious parent processes.

MITRE ATT&CK coverage

Telemetry coverage

Rule body

name: Shai-Hulud 2 Exfiltration Artifact Files
id: 9e7d3c0f-4a5b-6c8d-1e2f-3a4b5c6d7e8f
version: 4
creation_date: '2025-11-25'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: TTP
description: |
    Detects creation of exfiltration artifact files associated with Shai-Hulud 2.0 npm supply
    chain malware. The malware creates cloud.json, contents.json, environment.json, truffleSecrets.json,
    and actionsSecrets.json files containing harvested credentials from AWS, Azure, GCP, GitHub secrets,
    and environment variables. These files are staged before being pushed to attacker-controlled repositories.
data_source:
    - Sysmon for Linux EventID 11
    - Sysmon EventID 11
search: |
    | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime
    
    from datamodel=Endpoint.Filesystem where
    
    Filesystem.file_name IN (
      "cloud.json",
      "contents.json",
      "environment.json",
      "truffleSecrets.json",
      "actionsSecrets.json"
    )
    
    by Filesystem.action Filesystem.dest Filesystem.file_access_time Filesystem.file_create_time
       Filesystem.file_hash Filesystem.file_modify_time Filesystem.file_name Filesystem.file_path Filesystem.file_acl Filesystem.file_size Filesystem.process_guid Filesystem.process_id Filesystem.user
       Filesystem.vendor_product
    
    | `drop_dm_object_name(Filesystem)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `shai_hulud_2_exfiltration_artifact_files_filter`
how_to_implement: |
    The detection is based on data that originates from Endpoint Detection
    and Response (EDR) agents. These agents are designed to provide security-related
    telemetry from the endpoints where the agent is installed. To implement this search,
    you must ingest logs that contain filesystem events, specifically file creation
    events. These logs must be processed using the appropriate Splunk Technology Add-ons
    that are specific to the EDR product. The logs must also be mapped to the `Filesystem`
    node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM)
    to normalize the field names and speed up the data modeling process.
known_false_positives: |
    Low but possible. Generic filenames like cloud.json or environment.json may appear in legitimate contexts. Correlate with npm install activity or suspicious parent processes.
references:
    - https://www.wiz.io/blog/shai-hulud-2-0-ongoing-supply-chain-attack
    - https://securelist.com/shai-hulud-worm-infects-500-npm-packages-in-a-supply-chain-attack/117547/
finding:
    title: Shai-Hulud 2.0 exfiltration artifact $file_name$ created on $dest$
    entity:
        field: dest
        type: system
        score: 50
threat_objects:
    - field: file_name
      type: file_name
analytic_story:
    - NPM Supply Chain Compromise
asset_type: Endpoint
mitre_attack_id:
    - T1074.001
    - T1552.001
    - T1195.002
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint

Stages and Predicates

Stage 1: tstats

| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime

from datamodel=Endpoint.Filesystem where

Filesystem.file_name IN (
  "cloud.json",
  "contents.json",
  "environment.json",
  "truffleSecrets.json",
  "actionsSecrets.json"
)

by Filesystem.action Filesystem.dest Filesystem.file_access_time Filesystem.file_create_time
   Filesystem.file_hash Filesystem.file_modify_time Filesystem.file_name Filesystem.file_path Filesystem.file_acl Filesystem.file_size Filesystem.process_guid Filesystem.process_id Filesystem.user
   Filesystem.vendor_product

Stage 2: search

| `drop_dm_object_name(Filesystem)`

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `shai_hulud_2_exfiltration_artifact_files_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Filesystem.file_namein
  • "actionsSecrets.json"
  • "cloud.json"
  • "contents.json"
  • "environment.json"
  • "truffleSecrets.json"
field:"file_name" kind:in