HOMETHREATSUnidentified 099 (APT29 Dropbox Loader)
MALWARE FAMILY🕵️ ESPIONAGEADVANCED

Unidentified 099 (APT29 Dropbox Loader)

Internal ID: win.unidentified_099
1
aliases
Last seen:Mar 17, 2026

Intelligence Profile

This malware uses DropBox for C2 and was spread via spear-phishing attack at government organizations. It is different from win.boombox, which is another APT29 attributed malware using DropBox (written in .NET).

Threat Analysis

Unidentified 099 (APT29 Dropbox Loader) is a malware family tracked by threat intelligence researchers and catalogued in the Malpedia dataset. It represents a distinct malicious software lineage with identifiable code characteristics, behaviors, and victimology.

The group's espionage-oriented operations suggest a state-sponsored or state-aligned mandate, typically focused on stealing intellectual property, government secrets, or military intelligence. Targets are usually selected for strategic value rather than financial gain.

Classified as an advanced threat actor, Unidentified 099 (APT29 Dropbox Loader) likely develops or acquires zero-day exploits, employs custom malware toolchains, and demonstrates long-term persistence capabilities — hallmarks of a well-resourced operation consistent with nation-state backing.

External References

Quick Facts

TypeMalware Family
Motivation🕵️ espionage
Sophisticationadvanced
Aliases1

Also Known As

win.unidentified_099

Research Links

Data sourced from Malpedia, Ransomware.live, RansomLook, and CTIWATCH OSINT collection. Actor attribution is based on available intelligence and may be incomplete.