Suspicious CloudScout hxkz_zip Exfiltration Archive Creation via File System

ATT&CK techniques

Cred Access → Collection

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1539Steal Web Session Cookie
Discovery
Lateral Movement
Collection
- T1560Archive Collected Data
C2
Exfiltration
Impact

What it detects

This rule detects creation of files with the .hxkz_zip extension, the custom archive format CloudScout produces to stage stolen browser cookies and cloud session data before exfiltration. This extension is unique to the tooling and is not produced by legitimate software. Its presence indicates collection of session tokens for cloud-service hijacking.

Reporting behind it

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Suspicious CloudScout hxkz_zip Exfiltration Archive Creation via File System

Pivot detection · T1539 · 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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