Analysis and Detection of CLOUD#REVERSER: An Attack Involving Threat Actors Compromising Systems Using A Sophisticated Cloud-Based Malware
2024-05-21 • Securonix •
CLOUD#REVERSER uses phishing-delivered ZIP archives and an executable disguised as an Excel file to install a multi-stage VBScript and PowerShell infection chain. The malware persists through scheduled tasks that mimic Google update jobs, repeatedly executing payloads from `C:\ProgramData` while abusing Dropbox and Google Drive APIs for staging, command retrieval, script self-updates, and data exfiltration. Securonix observed a later-stage PowerShell component that downloaded a gzip-compressed payload, loaded it in memory via .NET reflection, and connected to `159.100.13.216:6606` for hands-on command execution. The article notes overlap in cloud-storage abuse with the earlier DEEP#GOSU campaign associated with North Korean Kimsuky, but it does not firmly attribute CLOUD#REVERSER itself to a DPRK actor.
Indicators of Compromise
| Type | Value | First Seen | Last Seen |
|---|---|---|---|
| IPv4 | 159.100.13.216 | 2024-09-05 | 2025-03-12 |
| HASH | f4275b0d3c4b6f3a165984b862f4890… | 2024-11-19 | 2024-11-19 |