Malicious Silver Fox Stealer Exfiltration Using WhatsAppBackup User Agent

ATT&CK techniques

Exfiltration

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
- T1567.002Exfiltration to Cloud Storage
Impact

What it detects

This rule detects outbound requests using the WhatsAppBackup 1.0 user agent associated with the Silver Fox Python stealer. The stealer uploads collected victim data to a web service while presenting this custom agent. Because no legitimate WhatsApp client uses this string it is a reliable exfiltration indicator.

Reporting behind it

Related detections9 linkedT1567.002 — drag to rearrange

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Malicious Silver Fox Stealer Exfiltration Using WhatsAppBackup User Agent

Pivot detection · T1567.002 · 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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