
Threat Group-3390
Also known as:Earth Smilodon · TG-3390 · Emissary Panda · BRONZE UNION · APT27 · Iron Tiger · LuckyMouse · Linen Typhoon
Overview
Threat Group-3390 is a Chinese threat group that has extensively used strategic Web compromises to target victims. The group has been active since at least 2010 and has targeted organizations in the aerospace, government, defense, technology, energy, manufacturing and gambling/betting sectors.
Naming & attribution
Threat Group-3390 is tracked under 9 names across the industry. It uses 57 documented ATT&CK techniques — more than 88% of the 174 groups tracked here. Activity attributed since at least 2010.
| Name | First reported by |
|---|---|
| Earth Smilodon | Lunghi, D. and Lu, K |
| TG-3390 | Dell SecureWorks Counter Threat Unit Threat Intelligence |
| Emissary Panda | Gallagher, S. |
| BRONZE UNION | Counter Threat Unit Research Team |
| APT27 | Pantazopoulos, N., Henry T |
| Iron Tiger | Khandelwal, S |
| LuckyMouse | Legezo, D |
| Linen Typhoon | Microsoft |
Distinctive techniques
Techniques this group uses that are rare across the other 173 tracked groups — these carry more signal than the near-universal ones.
T1070.005Network Share Connection Removal — used by 1 of 174 groupsT1560.002Archive via Library — used by 2 of 174 groupsT1608.002Upload Tool — used by 2 of 174 groupsT1685.001Disable or Modify Windows Event Log — used by 2 of 174 groupsT1053.002At — used by 3 of 174 groups
Closest groups by technique overlap
Computed from shared ATT&CK techniques. Overlap is not attribution — distinct actors converge on the same tradecraft — but a high share is a useful pivot.
- menuPass China — 28 shared techniques (37% overlap)
- OilRig Iran — 32 shared techniques (32% overlap)
- Dragonfly Russia — 27 shared techniques (31% overlap)
- APT32 Vietnam — 30 shared techniques (29% overlap)
- APT41 China — 30 shared techniques (28% overlap)
- GALLIUM China — 19 shared techniques (28% overlap)
Targets
Defense · Government · Private sector · Technology
Regions
Australia · Canada · China · France · India · Iran · Israel · Japan · Russia · South Korea · Taiwan · Thailand · Turkey · United Kingdom · United States
Capabilities
- Supply-chain compromise — ATT&CK T1195.002
- Exploitation of public-facing / client applications — ATT&CK T1190, T1203
- Custom malware/implant development — ATT&CK: 12 attributed custom malware families
TTPs — 57 techniques across 13 tactics
Resource Development
T1583.001DomainsT1588.002ToolT1588.003Code Signing CertificatesT1608.001Upload MalwareT1608.002Upload ToolT1608.004Drive-by Target
Initial Access
T1189Drive-by CompromiseT1190Exploit Public-Facing ApplicationT1195.002Compromise Software Supply ChainT1199Trusted RelationshipT1566.001Spearphishing Attachment
Execution
T1047Windows Management InstrumentationT1053.002AtT1059.001PowerShellT1059.003Windows Command ShellT1203Exploitation for Client ExecutionT1204.002Malicious File
Persistence
T1133External Remote ServicesT1505.003Web ShellT1543.003Windows ServiceT1547.001Registry Run Keys / Startup Folder
Privilege Escalation
Stealth
T1027.002Software PackingT1027.013Encrypted/Encoded FileT1027.015CompressionT1055.012Process HollowingT1070.004File DeletionT1070.005Network Share Connection RemovalT1078Valid AccountsT1140Deobfuscate/Decode Files or InformationT1574.001DLL
Defense Impairment
T1112Modify RegistryT1685.001Disable or Modify Windows Event Log
Credential Access
T1003.001LSASS MemoryT1003.002Security Account ManagerT1003.004LSA SecretsT1555.005Password Managers
Discovery
Lateral Movement
T1021.006Windows Remote ManagementT1210Exploitation of Remote Services
Collection
T1005Data from Local SystemT1056.001KeyloggingT1074.001Local Data StagingT1074.002Remote Data StagingT1119Automated CollectionT1560.002Archive via Library
Command and Control
T1071.001Web ProtocolsT1105Ingress Tool Transfer
Exfiltration
T1030Data Transfer Size LimitsT1567.002Exfiltration to Cloud Storage
Tools & malware (24)
Net · Systeminfo · gsecdump · PlugX · ASPXSpy · Cobalt Strike · Mimikatz · Impacket · gh0st RAT · certutil · China Chopper · HTTPBrowser · Tasklist · netstat · SysUpdate · HyperBro · ZxShell · RCSession · ipconfig · Clambling · pwdump · NBTscan · Pandora · Windows Credential Editor
Reporting (3)
- How Microsoft names threat actors — Microsoft
- Iron Tiger APT Updates Toolkit With Evolved SysUpdate Malware — Lunghi, D. and Lu, K
- Uncovering DRBControl — Lunghi, D. et al