Analytics Story: Silver Sparrow

Date: 2021-02-24 ID: cb4f48fe-7699-11eb-af77-acde48001122 Author: Michael Haag, Splunk Product: Splunk Enterprise Security

Description

Silver Sparrow, identified by Red Canary Intelligence, is a new forward looking MacOS (Intel and M1) malicious software downloader utilizing JavaScript for execution and a launchAgent to establish persistence.

Why it matters

Silver Sparrow works is a dropper and uses typical persistence mechanisms on a Mac. It is cross platform, covering both Intel and Apple M1 architecture. To this date, no implant has been downloaded for malicious purposes. During installation of the update.pkg or updater.pkg file, the malicious software utilizes JavaScript to generate files and scripts on disk for persistence.These files later download a implant from an S3 bucket every hour. This analytic assists with identifying different types of macOS malware families establishing LaunchAgent persistence. Per SentinelOne source, it is predicted that Silver Sparrow is likely selling itself as a mechanism to 3rd party affiliates or pay-per-install (PPI) partners, typically seen as commodity adware/malware. Additional indicators and behaviors may be found within the references.

Detections

Name ▲▼	Technique ▲▼	Type ▲▼
Suspicious Curl Network Connection	Ingress Tool Transfer	TTP
Suspicious PlistBuddy Usage	Launch Agent, Create or Modify System Process	TTP
Suspicious PlistBuddy Usage via OSquery	Launch Agent, Create or Modify System Process	TTP
Suspicious SQLite3 LSQuarantine Behavior	Data Staged	TTP

Data Sources

Name ▲▼	Platform ▲▼	Sourcetype ▲▼	Source ▲▼
CrowdStrike ProcessRollup2	N/A	`crowdstrike:events:sensor`	`crowdstrike`
Sysmon EventID 1	Windows	`xmlwineventlog`	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`
Windows Event Log Security 4688	Windows	`xmlwineventlog`	`XmlWinEventLog:Security`

References

Source: GitHub | Version: 1