Detectionmediumtest
Potentially Suspicious Execution Of Regasm/Regsvcs With Uncommon Extension
Detects potentially suspicious execution of the Regasm/Regsvcs utilities with an uncommon extension.
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Nasreddine Bencherchali (Nextron Systems)Created Mon Feb 13e9f8f8cc-07cc-4e81-b724-f387db9175e4windows
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_img:
- Image|endswith:
- '\Regsvcs.exe'
- '\Regasm.exe'
- OriginalFileName:
- 'RegSvcs.exe'
- 'RegAsm.exe'
selection_extension:
CommandLine|contains:
# Note: Add more potentially uncommon extensions
- '.dat'
- '.gif'
- '.jpeg'
- '.jpg'
- '.png'
- '.txt'
condition: all of selection_*False Positives
Unknown
False positive likelihood has not been assessed. Additional context may be needed during triage.
MITRE ATT&CK
Tactics
Sub-techniques
Rule Metadata
Rule ID
e9f8f8cc-07cc-4e81-b724-f387db9175e4
Status
test
Level
medium
Type
Detection
Created
Mon Feb 13
Path
rules/windows/process_creation/proc_creation_win_regasm_regsvcs_uncommon_extension_execution.yml
Raw Tags
attack.defense-evasionattack.t1218.009