Detectionmediumtest

Arbitrary File Download Via MSOHTMED.EXE

Detects usage of "MSOHTMED" to download arbitrary files

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Nasreddine Bencherchali (Nextron Systems)Created Fri Aug 19Updated Thu Nov 09459f2f98-397b-4a4a-9f47-6a5ec2f1c69dwindows
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: '\MSOHTMED.exe'
        - OriginalFileName: 'MsoHtmEd.exe'
    selection_cli:
        CommandLine|contains:
            - 'ftp://'
            - 'http://'
            - 'https://'
    condition: all of selection_*
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

Rule Metadata
Rule ID
459f2f98-397b-4a4a-9f47-6a5ec2f1c69d
Status
test
Level
medium
Type
Detection
Created
Fri Aug 19
Modified
Thu Nov 09
Path
rules/windows/process_creation/proc_creation_win_msohtmed_download.yml
Raw Tags
attack.defense-evasionattack.executionattack.t1218
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