Malicious Silver Fox Scheduled Task Persistence via AppClient (via process_creation)

ATT&CK techniques

Execution → Priv Esc

Recon
Resource Dev
Initial Access
Execution
- T1053.005Scheduled Task
Persistence
- T1053.005Scheduled Task
Priv Esc
- T1053.005Scheduled Task
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects schtasks.exe creating a minute interval task named AppClient, the persistence mechanism used by the Silver Fox ABCDoor backdoor to repeatedly relaunch itself. The high frequency task keeps the implant resident after a tax notification phishing compromise. Detecting the AppClient task creation surfaces backdoor persistence.

Reporting behind it

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Malicious Silver Fox Scheduled Task Persistence via AppClient (via process_creation)

Pivot detection · T1053.005 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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