Boot or Logon Autostart Execution: Winlogon Helper DLL T1547.004

Tactics: Persistence, Privilege Escalation

Adversaries may abuse features of Winlogon to execute DLLs and/or executables when a user logs in. Winlogon.exe is a Windows component responsible for actions at logon/logoff as well as the secure attention sequence (SAS) triggered by Ctrl-Alt-Delete. Registry entries in HKLM\Software[\\Wow6432Node\\]\Microsoft\Windows NT\CurrentVersion\Winlogon\ and HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\ are used to manage additional helper programs and functionalities that support Winlogon.

Events covered

7 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 8 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (11 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

FieldRulesHowSample values
EventID4eq 41, 12, 13, 4103, 4104
Details2ends_with 1, is_not_null 1.dll
TargetObject2ends_with 1, wildcard 1\registry\machine\software\microsoft\windows\currentversi..., \registry\machine\software\microsoft\windows\currentversion\run\*, \registry\machine\software\microsoft\windows\currentversi..., \software\microsoft\windows...
parent_process_name2regex_match 2(?i)winlogon\.exe
CommandLine1regex_match 1(?i)CurrentVersion\x5cWinlogon
ScriptBlockText1contains 1currentversion\winlogon, new-item, set-itemproperty
Type1eq 1
endpoint1eq 1IRemoteWinspool, ISecLogon, spoolss
event.type1eq 1change
operation1eq 1RpcAddMonitor, RpcAddPrintProcessor, RpcAsyncAddMonitor
process_name1eq 1wmiprvse.exe

Top indicator values (72 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

FieldKindValueRules (here)Corpus reach
parent_process_nameregex_match
(?i)winlogon\.exe
23
CommandLineregex_match
(?i)CurrentVersion\x5cWinlogon
1
Detailsends_with
.dll
18
EventIDeq
1
1237
EventIDeq
12
19
EventIDeq
13
122
EventIDeq
4103
1105
EventIDeq
4104
1268
EventIDeq
4688
1313
ScriptBlockTextcontains
currentversion\winlogon
1
ScriptBlockTextcontains
new-item
1
ScriptBlockTextcontains
set-itemproperty
1
TargetObjectends_with
\software\microsoft\windows nt\currentversion\winlogon\notify\logon
1
TargetObjectwildcard
\registry\machine\software\microsoft\windows\currentversion\policies\explorer\run\*
1
TargetObjectwildcard
\registry\machine\software\microsoft\windows\currentversion\run\*
1
TargetObjectwildcard
\registry\machine\software\microsoft\windows\currentversion\runonce\*
1
TargetObjectwildcard
\registry\machine\software\microsoft\windows\currentversion\runonceex\*
1
TargetObjectwildcard
\registry\machine\software\wow6432node\microsoft\windows\currentversion\run\*
1
TargetObjectwildcard
\registry\machine\system\*controlset*\services\*\imagepath
12
TargetObjectwildcard
\registry\machine\system\*controlset*\services\*\servicedll
1
TargetObjectwildcard
\registry\user\*\environment\userinitmprlogonscript
1
TargetObjectwildcard
\registry\user\*\software\microsoft\command processor\autorun
1
TargetObjectwildcard
\registry\user\*\software\microsoft\ctf\langbaraddin\*\filepath
1
TargetObjectwildcard
\registry\user\*\software\microsoft\internet explorer\extensions\*\exec
1
TargetObjectwildcard
\registry\user\*\software\microsoft\internet explorer\extensions\*\script
1
TargetObjectwildcard
\registry\user\*\software\microsoft\windows nt\currentversion\windows\load
1
TargetObjectwildcard
\registry\user\*\software\microsoft\windows nt\currentversion\winlogon\shell
1
TargetObjectwildcard
\registry\user\*\software\microsoft\windows nt\currentversion\winlogon\shell\*
1
TargetObjectwildcard
\registry\user\*\software\microsoft\windows\currentversion\policies\explorer\run\*
1
TargetObjectwildcard
\registry\user\*\software\microsoft\windows\currentversion\policies\system\shell
1

Exclusions (1 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

FieldKindValueRules excluding
process_nameregex_match
(?i)\x5cwindows\x5csystem32\x5c(atbroker|logonui|dwm|fontdrvhost|userinit|con...
2

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Platform (all)
Domain (all)

Sigma 3 rules

Elastic 1 rule

Splunk 4 rules