Potential Privilege Escalation Attempt Via .Exe.Local Technique

Severity: high
Author: Nasreddine Bencherchali (Nextron Systems), Subhash P (@pbssubhash)
Source: upstream

Detects potential privilege escalation attempt via the creation of the "*.Exe.Local" folder inside the "System32" directory in order to sideload "comctl32.dll"

Event coverage

Provider	Event ID	Title
Sysmon	11	FileCreate

Stages and Predicates

Stage 1: `selection`

or:
TargetFilename|startswith: 'C:\Windows\System32\consent.exe.local'
TargetFilename|startswith: 'C:\Windows\System32\logonUI.exe.local'
TargetFilename|startswith: 'C:\Windows\System32\narrator.exe.local'
TargetFilename|startswith: 'C:\Windows\System32\werFault.exe.local'
TargetFilename|startswith: 'C:\Windows\System32\wermgr.exe.local'
TargetFilename|endswith: '\comctl32.dll'

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.

Field	Kind	Values
`TargetFilename`	ends_with	`\comctl32.dll` corpus 2 (sigma 2)
`TargetFilename`	starts_with	`C:\Windows\System32\consent.exe.local` `C:\Windows\System32\logonUI.exe.local` `C:\Windows\System32\narrator.exe.local` `C:\Windows\System32\werFault.exe.local` `C:\Windows\System32\wermgr.exe.local`

Potential Privilege Escalation Attempt Via .Exe.Local Technique

Event coverage

Stages and Predicates

Stage 1: selection

Indicators

Stage 1: `selection`