Azure-Sentinel/Detections/SecurityEvent/AccessibilityFeaturesModifi...

74 строки
3.9 KiB
YAML

id: d714ef62-1a56-4779-804f-91c4158e528d
name: Modification of Accessibility Features
description: |
'Adversaries may establish persistence and/or elevate privileges by executing malicious content triggered by accessibility features. Windows contains accessibility features that may be launched with a key combination before a user has logged in (ex: when the user is on the Windows logon screen). An adversary can modify the way these programs are launched to get a command prompt or backdoor without logging in to the system.
Two common accessibility programs are C:\Windows\System32\sethc.exe, launched when the shift key is pressed five times and C:\Windows\System32\utilman.exe, launched when the Windows + U key combination is pressed. The sethc.exe program is often referred to as "sticky keys", and has been used by adversaries for unauthenticated access through a remote desktop login screen. [1]
Ref: https://attack.mitre.org/techniques/T1546/008/'
severity: Medium
requiredDataConnectors:
- connectorId: SecurityEvents
dataTypes:
- SecurityEvent
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
- Persistence
relevantTechniques:
- T1546.008
query: |
let ImagesList = dynamic (["sethc.exe","utilman.exe","osk.exe","Magnify.exe","Narrator.exe","DisplaySwitch.exe","AtBroker.exe"]);
let OriginalFileNameList = dynamic (["sethc.exe","utilman.exe","osk.exe","Magnify.exe","Narrator.exe","DisplaySwitch.exe","AtBroker.exe","SR.exe","utilman2.exe","ScreenMagnifier.exe"]);
Event
| where EventLog == "Microsoft-Windows-Sysmon/Operational" and EventID==1
| parse EventData with * 'ProcessId">' ProcessId "<" * 'Image">' Image "<" * 'OriginalFileName">' OriginalFileName "<" *
| where Image has_any (ImagesList) and not (OriginalFileName has_any (OriginalFileNameList))
| parse EventData with * 'ProcessGuid">' ProcessGuid "<" * 'Description">' Description "<" * 'CommandLine">' CommandLine "<" * 'CurrentDirectory">' CurrentDirectory "<" * 'User">' User "<" * 'LogonGuid">' LogonGuid "<" * 'Hashes">' Hashes "<" * 'ParentProcessGuid">' ParentProcessGuid "<" * 'ParentImage">' ParentImage "<" * 'ParentCommandLine">' ParentCommandLine "<" * 'ParentUser">' ParentUser "<" *
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by EventID, Computer, User, ParentImage, ParentProcessGuid, ParentCommandLine, ParentUser, Image, ProcessId, ProcessGuid, CommandLine, Description, OriginalFileName, CurrentDirectory, Hashes
| extend HostName = tostring(split(Computer, ".")[0]), DomainIndex = toint(indexof(Computer, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Computer, DomainIndex + 1), Computer)
| extend AccountName = tostring(split(User, "\\")[1]), AccountNTDomain = tostring(split(User, "\\")[0])
| extend ImageFileName = tostring(split(Image, "\\")[-1])
| extend ImageDirectory = replace_string(Image, ImageFileName, "")
| project-away DomainIndex
entityMappings:
- entityType: Process
fieldMappings:
- identifier: CommandLine
columnName: CommandLine
- identifier: ProcessId
columnName: ProcessId
- entityType: Host
fieldMappings:
- identifier: FullName
columnName: Computer
- identifier: HostName
columnName: HostName
- identifier: DnsDomain
columnName: HostNameDomain
- entityType: Account
fieldMappings:
- identifier: FullName
columnName: User
- identifier: Name
columnName: AccountName
- identifier: NTDomain
columnName: AccountNTDomain
- entityType: File
fieldMappings:
- identifier: Name
columnName: ImageFileName
- identifier: Directory
columnName: ImageDirectory
version: 1.0.3
kind: Scheduled
metadata:
source:
kind: Community
author:
name: Vasileios Paschalidis
support:
tier: Community
categories:
domains: [ "Security - Others" ]