Malicious PolarEdge QNAP Backdoor Dropper Script in Temp (via file_event)

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of the hidden dropper script used by the PolarEdge QNAP backdoor in the temp directory. After exploiting CVE-2023-20118 the implant writes a hidden qnax shell script to stage its components. A hidden script with this name in tmp is a specific artifact of the PolarEdge implant.

Reporting behind it

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Malicious PolarEdge QNAP Backdoor Dropper Script in Temp (via file_event)

Pivot detection · T1140 · 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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