Detectionhightest
Base64 MZ Header In CommandLine
Detects encoded base64 MZ header in the commandline
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Launch
Nasreddine Bencherchali (Nextron Systems)Created Tue Jul 1222e58743-4ac8-4a9f-bf19-00a0428d8c5fwindows
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 Logic1 selector
detection:
selection:
CommandLine|contains:
- 'TVqQAAMAAAAEAAAA' # MZ..........
- 'TVpQAAIAAAAEAA8A'
- 'TVqAAAEAAAAEABAA'
- 'TVoAAAAAAAAAAAAA'
- 'TVpTAQEAAAAEAAAA'
condition: selectionFalse Positives
Unlikely
False positives are unlikely for most environments. High confidence detection.
References
MITRE ATT&CK
Tactics
Rule Metadata
Rule ID
22e58743-4ac8-4a9f-bf19-00a0428d8c5f
Status
test
Level
high
Type
Detection
Created
Tue Jul 12
Path
rules/windows/process_creation/proc_creation_win_susp_inline_base64_mz_header.yml
Raw Tags
attack.execution