Windows SoftEther VPN Masquerading as Legitimate Binary
Flax Typhoon actors have been identified downloading and using SoftEther VPN software to obfuscate their activity. This searches for the SoftEther VPN binary running with the obfuscated binary names they use for the…
Description
Flax Typhoon actors have been identified downloading and using SoftEther VPN software to obfuscate their activity. This searches for the SoftEther VPN binary running with the obfuscated binary names they use for the process.
Detection logic
Detection requirements
- Platform
- ContainersESXiLinuxmacOSWindows
The rule states no platform. This is derived from the 2 ATT&CK techniques it maps to.
- Log source category
- sysmon_eventid_1
Known benign triggers
- Some legitimate users may run SoftEther VPN for remote access or privacy purposes. Exclude known approved VPN usage to reduce false alerts.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.microsoft.com/en-us/security/blog/2023/08/24/flax-typhoon-using-legitimate-software-to-quietly-access-taiwanese-organizations/ | 3from 2 sources |
From the source
- At source
- Open at source
- Upstream identifier
- 69fe4cb7-807e-4012-a17f-cd288215b038
- Tagged by the source as
- Flax TyphoonLinux Persistence TechniquesLinux Privilege EscalationEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1