Suspicious Downloader Writing to Public Libraries Directory

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects download utilities such as bitsadmin, certutil, or curl retrieving files into the Public Libraries directory, a staging location used by the Tomiris APT. The actors fetched Havoc and AdaptixC2 payloads into $public\libraries to blend with rarely inspected shared folders. Using a download LOLBin to write into the Public user profile is a strong indicator of ingress tool transfer for later execution.

Reporting behind it

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Suspicious Downloader Writing to Public Libraries Directory

Pivot detection · T1105 · 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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