Malicious WinRAR CVE-2023-38831 Script Host Child Process via Process Chain (via process_creation)

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1059Command and Scripting Interpreter
- T1203Exploitation for Client Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects WinRAR.exe spawning command interpreters or script hosts such as cmd, powershell, mshta or rundll32, which indicates exploitation of the CVE-2023-38831 archive spoofing zero-day. It is associated with attacks abusing the WinRAR file extension spoofing vulnerability reported by Uptycs. When a user opens a benign-looking file in a crafted archive, WinRAR executes an accompanying malicious script, so these child processes reliably flag exploitation.

Reporting behind it

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Malicious WinRAR CVE-2023-38831 Script Host Child Process via Process Chain (via process_creation)

Pivot detection · T1059 · 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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