Detection rules › Splunk

Wow6432Node Classes Autorun Keys Modification (Windows Event Log)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

Adversaries may achieve persistence by adding a program to a startup folder or referencing it with a Registry run key. Adding an entry to the "run keys" in the Registry or startup folder will cause the program referenced to be executed when a user logs in. These programs will be executed under the context of the user and will have the account's associated permissions level. This use case detects any modifications made to the \Software\Wow6432Node\Classes registry path, indicating modification of autostart extensibility point (ASEP).

MITRE ATT&CK coverage

References

Event coverage

Rule body yaml

id: '32506.57765'
title: Wow6432Node Classes Autorun Keys Modification
description: Adversaries may achieve persistence by adding a program to a startup
  folder or referencing it with a Registry run key. Adding an entry to the "run keys"
  in the Registry or startup folder will cause the program referenced to be executed
  when a user logs in. These programs will be executed under the context of the user
  and will have the account's associated permissions level. This use case detects
  any modifications made to the \Software\Wow6432Node\Classes registry path, indicating
  modification of autostart extensibility point (ASEP).
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` ((TERM(EventCode=4657) OR
  "<EventID>4657<") OR ((TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process)
  "ADD" OR "Set-ItemProperty" OR "sp " OR "New-ItemProperty" OR "New-Item" OR "md
  " OR "ni ")) "SOFTWARE\\Wow6432Node\\Classes" ("\\Folder\\ShellEx\\ExtShellFolderViews"
  OR "\\Folder\\ShellEx\\DragDropHandlers" OR "\\Folder\\ShellEx\\ColumnHandlers"
  OR "\\Directory\\Shellex\\DragDropHandlers" OR "\\Directory\\Shellex\\CopyHookHandlers"
  OR "\\CLSID\\{AC757296-3522-4E11-9862-C17BE5A1767E}\\Instance" OR "\\CLSID\\{ABE3B9A4-257D-4B97-BD1A-294AF496222E}\\Instance"
  OR "\\CLSID\\{7ED96837-96F0-4812-B211-F13C24117ED3}\\Instance" OR "\\CLSID\\{083863F1-70DE-11d0-BD40-00A0C911CE86}\\Instance"
  OR "\\AllFileSystemObjects\\ShellEx\\DragDropHandlers" OR "\\ShellEx\\PropertySheetHandlers"
  OR "\\ShellEx\\ContextMenuHandlers") | table _time, host, user, process, process_*,
  parent_* | bin span=1s | stats values(*) as * by _time, host '
techniques:
- persistence:boot or logon autostart execution:registry run keys / startup folder
- privilege-escalation:boot or logon autostart execution:registry run keys / startup
  folder
technique_id:
- T1547.001
data_category:
- Process command-line parameters
- Windows event logs
- Windows Registry
references:
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/registry/registry_set/registry_set_asep_reg_keys_modification_wow6432node.yml
- https://docs.microsoft.com/en-us/sysinternals/downloads/autoruns

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_winevent` ((TERM(EventCode=4657) OR "<EventID>4657<") OR ((TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) "ADD" OR "Set-ItemProperty" OR "sp " OR "New-ItemProperty" OR "New-Item" OR "md " OR "ni ")) "SOFTWARE\\Wow6432Node\\Classes" ("\\Folder\\ShellEx\\ExtShellFolderViews" OR "\\Folder\\ShellEx\\DragDropHandlers" OR "\\Folder\\ShellEx\\ColumnHandlers" OR "\\Directory\\Shellex\\DragDropHandlers" OR "\\Directory\\Shellex\\CopyHookHandlers" OR "\\CLSID\\{AC757296-3522-4E11-9862-C17BE5A1767E}\\Instance" OR "\\CLSID\\{ABE3B9A4-257D-4B97-BD1A-294AF496222E}\\Instance" OR "\\CLSID\\{7ED96837-96F0-4812-B211-F13C24117ED3}\\Instance" OR "\\CLSID\\{083863F1-70DE-11d0-BD40-00A0C911CE86}\\Instance" OR "\\AllFileSystemObjects\\ShellEx\\DragDropHandlers" OR "\\ShellEx\\PropertySheetHandlers" OR "\\ShellEx\\ContextMenuHandlers")

Stage 2: table

| table _time, host, user, process, process_*, parent_*

Stage 3: bucket

| bin span=1s

Stage 4: stats

| stats values(*) as * by _time, host

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventCodeeq
  • 4657 corpus 17 (splunk 14, kusto 3)
  • 4688 corpus 313 (splunk 283, kusto 30)

Search terms

Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.

StageTerm
1TERM
1"<EventID>4657<"
1TERM
1"<EventID>4688<"
1"ADD"
1"Set-ItemProperty"
1"sp "
1"New-ItemProperty"
1"New-Item"
1"md "
1"ni "
1"SOFTWARE\\Wow6432Node\\Classes"
1"\\Folder\\ShellEx\\ExtShellFolderViews"
1"\\Folder\\ShellEx\\DragDropHandlers"
1"\\Folder\\ShellEx\\ColumnHandlers"
1"\\Directory\\Shellex\\DragDropHandlers"
1"\\Directory\\Shellex\\CopyHookHandlers"
1"\\CLSID\\{AC757296-3522-4E11-9862-C17BE5A1767E}\\Instance"
1"\\CLSID\\{ABE3B9A4-257D-4B97-BD1A-294AF496222E}\\Instance"
1"\\CLSID\\{7ED96837-96F0-4812-B211-F13C24117ED3}\\Instance"
1"\\CLSID\\{083863F1-70DE-11d0-BD40-00A0C911CE86}\\Instance"
1"\\AllFileSystemObjects\\ShellEx\\DragDropHandlers"
1"\\ShellEx\\PropertySheetHandlers"
1"\\ShellEx\\ContextMenuHandlers"