
This Repository Talks about the Follina MSDT from Defender Perspective
This Repository Talks about the Follina MSDT from Defender Perspective
The bug is a Microsoft Windows Support Diagnostic Tool (MSDT) remote code execution vulnerability reported by crazyman of the Shadow Chaser Group. Microsoft is now tracking it as CVE-2022-30190. The flaw impacts all Windows versions still receiving security updates (Windows 7+ and Server 2008+).
As security researcher nao_sec found, it is used by threat actors to execute malicious PowerShell commands via MSDT in what Redmond describes as Arbitrary Code Execution (ACE) attacks when opening or previewing Word documents.
"An attacker who successfully exploits this vulnerability can run arbitrary code with the privileges of the calling application," Microsoft explains.
For doing Threat Hunt you can find the Sigma Rule HERE
Below are the Detection Rules which can be further tuned. Kudos to Bala Ganesh. Full article can be found HERE
MS Defender:
DeviceProcessEvents | where ((ProcessCommandLine contains "WINWORD.EXE") and (ProcessCommandLine contains "msdt.exe") and (ProcessCommandLine contains "sdiagnhost.exe" or ProcessCommandLine contains "csc.exe" or ProcessCommandLine contains "PCWDiagnostic" or ProcessCommandLine contains "IT_ReBrowserForFile" or ProcessCommandLine contains "IT_BrowserForFile" or ProcessCommandLine contains "conhost.exe"))
[Doc Malware]
alert.severity = 2
description = Detection (Rule ID: 74566a6a66aaasdq2ed)
cron_schedule = 0 * * * *
disabled = 1
is_scheduled = 1
is_visible = 1
dispatch.earliest_time = -60m@m
dispatch.latest_time = now
search = (source="WinEventLog:*" AND (CommandLine="*WINWORD.EXE*") AND (CommandLine="*msdt.exe*") AND (CommandLine="*sdiagnhost.exe*" OR CommandLine="*csc.exe*" OR CommandLine="*PCWDiagnostic*" OR CommandLine="*IT_ReBrowserForFile*" OR CommandLine="*IT_BrowserForFile*" OR CommandLine="*conhost.exe*"))
alert.suppress = 0
alert.track = 1
SELECT UTF8(payload) from events where LOGSOURCETYPENAME(devicetype)='Microsoft Windows Security Event Log' and ("Process CommandLine" ilike '%WINWORD.EXE%') and ("Process CommandLine" ilike '%msdt.exe%') and ("Process CommandLine" ilike '%sdiagnhost.exe%' or "Process CommandLine" ilike '%csc.exe%' or "Process CommandLine" ilike '%PCWDiagnostic%' or "Process CommandLine" ilike '%IT_ReBrowserForFile%' or "Process CommandLine" ilike '%IT_BrowserForFile%' or "Process CommandLine" ilike '%conhost.exe%')
(CommandLine.keyword:*WINWORD.EXE* AND CommandLine.keyword:*msdt.exe* AND CommandLine.keyword:(*sdiagnhost.exe* *csc.exe* *PCWDiagnostic* *IT_ReBrowserForFile* *IT_BrowserForFile* *conhost.exe*))
Sumologic
(_sourceCategory=*windows* AND (CommandLine = "*WINWORD.EXE*") AND (CommandLine = "*msdt.exe*") AND (CommandLine = "*sdiagnhost.exe*" OR CommandLine = "*csc.exe*" OR CommandLine = "*PCWDiagnostic*" OR CommandLine = "*IT_ReBrowserForFile*" OR CommandLine = "*IT_BrowserForFile*" OR CommandLine = "*conhost.exe*"))
(process.command_line:*WINWORD.EXE* AND process.command_line:*msdt.exe* AND process.command_line:(*sdiagnhost.exe* OR *csc.exe* OR *PCWDiagnostic* OR *IT_ReBrowserForFile* OR *IT_BrowserForFile* OR *conhost.exe*))
Below query described by Brent Murphy HERE can also be applied
process where event.type in ("start" , "process_created") and (process.pe.original_file_name : "msdt.exe" or process.name : "msdt.exe") and (process.parent.pe.original_file_name : ("winword.exe", "excel.exe", "outlook.exe", "powerpnt.exe") or process.parent.name : ("winword.exe", "excel.exe", "outlook.exe", "powerpnt.exe"))
# office processes spawning msdt.exe
config case_sensitive = false timeframe = 30d
| dataset = xdr_data
| filter event_type = ENUM.PROCESS and action_process_image_command_line contains "msdt.exe" and actor_process_image_name in ("winword.exe", "powerpnt.exe", "excel.exe", "msaccess.exe","visio.exe","onenote.exe","powershell.exe")
| fields agent_hostname , action_process_image_command_line , action_process_image_path , actor_process_command_line , actor_process_image_path , causality_actor_process_image_path
# msdt.exe execution with suspicious argument