Uacme

Overview

HackTool:Win32/Uacme (often detected due to its inclusion in the open-source **UACMe** repository) is a powerful, publicly available framework designed to bypass Windows User Account Control (UAC). While developed for security research and penetration testing, UACMe is heavily weaponized by threat actors and integrated into sophisticated malware (like ransomware and advanced RATs). It allows a process running with standard user privileges to silently escalate to high (Administrator) privileges without prompting the user with the familiar 'Do you want to allow this app to make changes?' dialog box.

Understanding UAC Bypasses
To an end-user, a successful UAC bypass is invisible; the malware simply gains administrative rights without asking. For a SOC, detecting UACMe usage indicates that an attacker has already gained initial access (as a standard user) and is actively escalating their privileges to fully compromise the host. The UACMe project currently catalogs over 70 distinct methods for bypassing UAC, constantly adapting as Microsoft patches older vulnerabilities.

Execution and Escalation Mechanics
Threat actors embed specific UACMe methods into their droppers (`T1548.002`). The most common techniques involve exploiting auto-elevating Windows executables (binaries signed by Microsoft that silently elevate without a prompt). For example, the attacker might drop a malicious DLL (`T1574.002`) into a specific system folder and then launch an auto-elevating Windows tool (like `sysprep.exe` or `cliconfg.exe`). Because the Windows tool is trusted, UAC elevates it silently; the tool then unknowingly loads the attacker's malicious DLL (DLL Hijacking), granting the attacker's code full administrative rights. Other methods involve complex COM interface hijacking or modifying specific registry keys (`HKCU\Software\Classes`) that trusted binaries read during execution.

Indicators of Compromise & Impact
The impact is Local Privilege Escalation (LPE), giving the attacker full control to disable AV, install rootkits, or dump credentials. Host-based IoCs include EDR alerts for anomalous DLL loads by trusted system processes (e.g., `sysprep.exe` loading a DLL from a non-standard path). Monitoring for sudden modifications to `HKCU\Software\Classes\mscfile\shell\open\command` or similar registry keys is critical. EDR systems should also flag any process spawning a high-integrity command prompt (`cmd.exe`) without a corresponding interactive user session.

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:

MITRE D3FEND™ Defensive Countermeasures

Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):

Tiered Detection Rules (Cisco CAIRN Model)

Modern threat detection requires multi-layered rule engineering. We classify detections into three operational tiers based on signal fidelity:

rule MALWARE_WIN_UACME_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Uacme"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "uacme" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Uacme (Ransomware) Execution & Triage
id: efb058ae-0f43-57a3-8443-58efce69d519
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Uacme malware family. Detects volume shadow copy deletion, boot status
  tampering, and recovery inhibition characteristic of modern ransomware operations.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/uacme
- https://malware-families-catalog.systemhelpdesk.com/defensive/ransomware-protection
- https://malware-families-catalog.systemhelpdesk.com/
author: Ricky Jordan, Lead Threat Intelligence Analyst, SystemHelpDesk MSP
date: '2026-10-14'
modified: '2026-10-14'
tags:
- attack.ransomware
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1574_002
- attack.t1546_015
- attack.t1548_002
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \vssadmin.exe
    - \wmic.exe
    - \wbadmin.exe
    - \bcdedit.exe
    CommandLine|contains:
    - delete shadows
    - shadowcopy delete
    - resize shadowstorage
    - recoveryenabled no
    - ignoreallfailures
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: critical

rule MALWARE_WIN_UACME_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Uacme tradecraft"
        tier = "T3 - Attribution Fingerprint"
        confidence = "High (Confirmed Family Signature)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        // Core family identifier & heuristic payload signatures
        $attrib_str = "uacme" ascii wide nocase
        $pe_magic = "MZ" ascii
        $net_marker = "http" ascii nocase
    condition:
        uint16(0) == 0x5a4d and ($attrib_str and $net_marker) and filesize < 15MB
}

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Immediately isolate the endpoint; if a UAC bypass was successful, the attacker now has full administrative control over the machine.
2. Assume local administrator credentials and LSA secrets have been compromised; initiate password resets and verify no new administrative accounts were created.
3. Analyze EDR process trees to determine *which* specific auto-elevating binary was abused, and use that information to hunt for lateral movement across the network.
4. Ensure the organization's Windows endpoints are fully patched, as Microsoft continually addresses the specific UAC bypass methods documented in the UACMe project.

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not assume that standard user accounts are secure simply because they are not administrators; UAC bypasses specifically target this gap.
2. Avoid lowering the UAC slider to 'Never Notify' in enterprise environments, as this effectively disables UAC and makes privilege escalation trivial for malware.

References & External Analysis

• Search "uacme" on VirusTotal (External Analysis)
• Search "uacme" on Any.Run (Sandbox Sandbox)
• Search "uacme" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Xpun
• Sage
• Malkryp
• Gottle
• Cslz
• Genasep
• Sonbokli
• Genericrxat

Machine-readable

Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/uacme.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.