Emerging Threatcriticaltest
Qakbot Rundll32 Fake DLL Extension Execution
Detects specific process tree behavior of a "rundll32" execution where the DLL doesn't have the ".dll" extension. This is often linked with potential Qakbot activity.
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Launch
X__Junior (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)Created Wed May 24bfd34392-c591-4009-b938-9fd985a28b852023
Emerging Threat
Active Threat
Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation
Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.
Detection Logic
Detection Logic2 selectors
detection:
selection:
ParentImage|endswith:
# Note: Only add processes seen used by Qakbot to avoid collision with other strains of malware
- '\cmd.exe'
- '\cscript.exe'
- '\curl.exe'
- '\mshta.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\wscript.exe'
Image|endswith: '\rundll32.exe'
CommandLine|contains:
# Note: Only add paths seen used by Qakbot to avoid collision with other strains of malware
- ':\ProgramData\'
- ':\Users\Public\'
- '\AppData\Local\Temp\'
- '\AppData\Roaming\'
filter_main_extension:
CommandLine|contains: '.dll'
condition: selection and not 1 of filter_main_*False Positives
Unlikely
False positives are unlikely for most environments. High confidence detection.
References
MITRE ATT&CK
Other
detection.emerging-threats
Rule Metadata
Rule ID
bfd34392-c591-4009-b938-9fd985a28b85
Status
test
Level
critical
Type
Emerging Threat
Created
Wed May 24
Path
rules-emerging-threats/2023/Malware/Qakbot/proc_creation_win_malware_qakbot_rundll32_fake_dll_execution.yml
Raw Tags
attack.defense-evasionattack.executiondetection.emerging-threats