Suspicious Vidar Second-Stage Download via Structured index.zip Dropzone Paths (via proxy)

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 HTTP requests for index.zip archives under file-type-segmented dropzone paths such as /pe/, /dll/, /py/, /ps/ and /bat/, the second-stage retrieval pattern used by an access-code-gated DocuSign-themed delivery chain that dropped the Vidar information stealer as analyzed by Joe Sandbox. Adversaries organize payload dropzones by artifact type behind an access gate, so requests matching this structured path layout indicate retrieval of a staged payload.

Reporting behind it

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Suspicious Vidar Second-Stage Download via Structured index.zip Dropzone Paths (via proxy)

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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