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Financially Motivated11 malware familiesExploits CVEs in the wild

Cinnamon Tempest

Also known asBRONZE STARLIGHTCinnamon TempestDEV-0401Emperor DragonflyHighGroundslime34

Cinnamon Tempest is a financially motivated, China-based activity group tracked by Microsoft as DEV-0401 and also referred to as Emperor Dragonfly and Bronze Starlight; aliases in the provided content also include Highground and SLIME34. Microsoft states it is unique among the human-operated ransomware actors it tracks in being confirmed as China-based. The group conducts hands-on ransomware intrusions and has handled initial access, lateral movement, and ransomware deployment itself. Reported initial access includes exploitation of unpatched public-facing applications and vulnerabilities in Exchange, ManageEngine AdSelfService Plus, Confluence, Log4j 2, and VMware Horizon. Observed tradecraft includes use of customized Impacket wmiexec.py and WMI for lateral movement, PowerShell for C2 communications, file download, and reconnaissance, batch scripts deployed via Group Policy Objects for ransomware execution, weaponized DLLs to load and decrypt payloads, protocol tunneling and proxying, and use of web shells and IIS components for persistence. The group has used open-source and customized tooling including the Iox proxy tool, NPS tunneling tool, Meterpreter, and a keylogger that uploaded captured keystroke logs to Alibaba Cloud Object Storage Service (Aliyun OSS). Microsoft also reported that the group frequently launched Cobalt Strike via DLL search order hijacking and began replacing Cobalt Strike with Sliver around June 2022. In 2022, Microsoft observed DEV-0401 deploying Pandora ransomware and later shifting to LockBit 2.0.

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MITRE ATT&CK

Tradecraft

42 distinct techniques observed across reporting, grouped by tactic. Hover any cell for the evidence excerpt; click through for MITRE's full description.

14 of 15 tactics67 techniques×N= number of intelligence reports citing this technique
MITRE ATT&CK
TA0042
Resource Development
2 techniques
T1588
Obtain Capabilities
T1588.002×2
Tool
T1608×2
Stage Capabilities
T1608.001
Upload Malware
T1608.002
Upload Tool
TA0001
Initial Access
3 techniques
T1078×4
Valid Accounts
T1078.002
Domain Accounts
T1133×3
External Remote Services
T1190×13
Exploit Public-Facing Application
TA0002
Execution
5 techniques
T1047×2
Windows Management Instrumentation
T1053
Scheduled Task/Job
T1053.005
Scheduled Task
T1059×2
Command and Scripting Interpreter
T1059.001×9
PowerShell
T1059.003×3
Windows Command Shell
T1129
Shared Modules
T1574
Hijack Execution Flow
T1574.001×3
DLL
TA0003
Persistence
6 techniques
T1053
Scheduled Task/Job
T1053.005
Scheduled Task
T1078×4
Valid Accounts
T1078.002
Domain Accounts
T1098
Account Manipulation
T1133×3
External Remote Services
T1505
Server Software Component
T1505.003×3
Web Shell
T1505.004
IIS Components
T1543
Create or Modify System Process
T1543.003×4
Windows Service
TA0004
Privilege Escalation
6 techniques
T1053
Scheduled Task/Job
T1053.005
Scheduled Task
T1055
Process Injection
T1078×4
Valid Accounts
T1078.002
Domain Accounts
T1098
Account Manipulation
T1484
Domain or Tenant Policy Modification
T1484.001×5
Group Policy Modification
T1543
Create or Modify System Process
T1543.003×4
Windows Service
TA0005
Stealth
3 techniques
T1055
Process Injection
T1078×4
Valid Accounts
T1078.002
Domain Accounts
T1574
Hijack Execution Flow
T1574.001×3
DLL
TA0112
Defense Impairment
1 technique
T1484
Domain or Tenant Policy Modification
T1484.001×5
Group Policy Modification
TA0006
Credential Access
2 techniques
T1187
Forced Authentication
T1557
Adversary-in-the-Middle
T1557.001
Name Resolution Poisoning and SMB Relay
TA0007
Discovery
4 techniques
T1012
Query Registry
T1069
Permission Groups Discovery
T1082
System Information Discovery
T1518
Software Discovery
TA0008
Lateral Movement
1 technique
T1021
Remote Services
T1021.001×2
Remote Desktop Protocol
T1021.002×3
SMB/Windows Admin Shares
T1021.003
Distributed Component Object Model
TA0009
Collection
1 technique
T1557
Adversary-in-the-Middle
T1557.001
Name Resolution Poisoning and SMB Relay
TA0011
Command and Control
4 techniques
T1071
Application Layer Protocol
T1090×5
Proxy
T1090.002
External Proxy
T1105×5
Ingress Tool Transfer
T1572×2
Protocol Tunneling
TA0010
Exfiltration
1 technique
T1567
Exfiltration Over Web Service
T1567.002×5
Exfiltration to Cloud Storage
TA0040
Impact
1 technique
T1486
Data Encrypted for Impact
WEAPONIZED

Associated vulnerabilities

9 CVEs this actor has used in observed campaigns. 9 of them exploited in the wild.

CVE-2025-9491Microsoft Windows LNK File UI Misrepresentation Remote Code Execution VulnerabilityIn the wildEvidence2

This detection identifies instances where Windows Explorer.exe spawns PowerShell or cmd.exe processes, particularly focusing on executions initiated by LNK files. This behavior is associated with the ZDI-CAN-25373 Windows shortcut zero-day vulnerability, where specially crafted LNK files are used to trigger malicious code execution through cmd.exe or powershell.exe. This technique has been actively exploited by multiple APT groups in targeted attacks through both HTTP and SMB delivery methods.

CVE-2021-31207Post-auth arbitrary file write in Microsoft Exchange Server (ProxyShell)In the wildEvidence1

This analytic identifies potential exploitation attempts of ProxyShell (CVE-2021-34473, CVE-2021-34523, CVE-2021-31207) and ProxyNotShell (CVE-2022-41040, CVE-2022-41082) vulnerabilities in Microsoft Exchange Server.

CVE-2021-34473ProxyShell pre-auth SSRF/authentication bypass in Microsoft Exchange AutodiscoverIn the wildEvidence1

This analytic identifies potential exploitation attempts of ProxyShell (CVE-2021-34473, CVE-2021-34523, CVE-2021-31207) and ProxyNotShell (CVE-2022-41040, CVE-2022-41082) vulnerabilities in Microsoft Exchange Server.

CVE-2021-34523Microsoft Exchange PowerShell Backend Elevation of Privilege (ProxyShell)In the wildEvidence1

This analytic identifies potential exploitation attempts of ProxyShell (CVE-2021-34473, CVE-2021-34523, CVE-2021-31207) and ProxyNotShell (CVE-2022-41040, CVE-2022-41082) vulnerabilities in Microsoft Exchange Server.

CVE-2021-44228Log4ShellIn the wildEvidence1

In February of 2022, DEV-0401 was observed deploying the Pandora ransomware family, primarily via unpatched VMware Horizon systems vulnerable to the Log4j 2 CVE-2021-44228 vulnerability.

4 more CVEs tied to this actor tracked in Mallory.

IOCS

Observables

5 indicators attributed to this actor: domains, IPs, hashes, and other artifacts pulled from reporting. View more in app.

IOC values are gated. View more in Mallory for domains, IPs, hashes, and other artifacts, or pipe them straight into your SIEM.

What this page doesn’t show

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Target overlap

Match sector + geo + tech-stack targeting against your real footprint.

Tradecraft mapping42

Every observed MITRE ATT&CK technique, grouped by tactic.

Malware arsenal11

Families this actor is known to deploy, with IOCs and behavior.

Exploited CVEs9

CVEs this actor has used in known campaigns.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Observables5

Domains, IPs, and hashes tied to this actor, refreshed continuously.