Malicious Bumblebee Loader User-Agent In Web Traffic

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects the hardcoded User-Agent string Bumblebee Loader in outbound web traffic, the beacon signature of the Bumblebee loader as it contacts its command-and-control server. Bumblebee stages Cobalt Strike and hands off access to ransomware affiliates. The self-identifying User-Agent uniquely marks infected hosts checking in.

Reporting behind it

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Malicious Bumblebee Loader User-Agent In Web Traffic

Pivot detection · T1071.001 · 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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