Bypass UAC via WSReset.exe

Severity: high
Author: E.M. Anhaus (originally from Atomic Blue Detections, Tony Lambert), oscd.community, Florian Roth
Source: upstream

Detects use of WSReset.exe to bypass User Account Control (UAC). Adversaries use this technique to execute privileged processes.

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	`T1548.002` Abuse Elevation Control Mechanism: Bypass User Account Control
Defense Evasion	`T1548.002` Abuse Elevation Control Mechanism: Bypass User Account Control

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `selection`

ParentImage|endswith: '\wsreset.exe'

Stage 2: `not filter`

or:
Image|endswith: '\conhost.exe'
OriginalFileName: CONHOST.EXE

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
`Image`	ends_with	`\conhost.exe` corpus 7 (sigma 7)
`OriginalFileName`	eq	`CONHOST.EXE` corpus 3 (sigma 3)
`ParentImage`	ends_with	`\wsreset.exe`