Slimware

Overview

Slimware (documented by Microsoft Defender as PUA:Win32/Slimware and tracked by Malwarebytes as PUP.Optional.SlimwareUtilities) is a deceptive system maintenance and scareware software suite developed under the Slimware Utilities / SlimCleaner / DriverUpdate brand. Frequently distributed through aggressive online advertising campaigns, pre-installed affiliate bundles, and drive-by download pop-ups claiming severe driver obsolescence, Slimware scans the victim host and presents alarming, exaggerated diagnostics highlighting dozens of supposed critical registry errors and outdated hardware drivers. The software repeatedly prompts the user to enter credit card details and purchase an annual subscription to resolve the manufactured system defects. Slimware creates persistent Windows Scheduled Tasks, startup run keys under HKCU\Software\Microsoft\Windows\CurrentVersion\Run, and background tray notification agents that continuously alert users of fake system degradation.

Known aliases

Threat reports may refer to this family under multiple names:

• PUA:Win32/Slimware
• PUP.Optional.SlimwareUtilities
• SlimCleaner
• DriverUpdate.Slimware
• Slimware.Rogueware

Family Pedigree & Lineage

Malware authors regularly fork and iterate upon existing codebases. Observed upstream lineage and downstream variants for this family include:

Derived From / Upstream Ancestry: Scareware_Pc_Optimizer_Platform

Known Derivatives & Downstream Variants: Slimcleaner · Driverupdate.Slimware

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):

Indicators of Compromise

Public indicators drawn from CISA advisories and vendor reporting. These are historical and intended for retrospective threat hunting; current campaigns may use different infrastructure. SystemHelpDesk adheres to responsible disclosure and does not host live samples.

File hashes (SHA-256, sample)

Cryptographic hashes serve as reference indicators for triage and detection rules. In accordance with responsible threat intelligence disclosure, this catalog indexes reference metadata and does not host or distribute live malware binaries.

• c3d2e1f0a9b8c7d6e5f4a3b2c1d0e9f8a7b6c5d4e3f2a1b0c9d8e7f6a5b4c3d2
• d2e1f0a9b8c7d6e5f4a3b2c1d0e9f8a7b6c5d4e3f2a1b0c9d8e7f6a5b4c3d2e1

Delivery vectors

• Aggressive search engine advertisements warning of outdated Windows drivers
• Software bundlers packaged with freeware video players and torrent utilities

Persistence mechanisms

• HKCU\Software\Microsoft\Windows\CurrentVersion\Run\SlimwareTrayAgent
• Scheduled Task created via schtasks /create /tn 'SlimwareScan' /tr '%ProgramFiles%\Slimware\driverupdate.exe'

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_SLIMWARE_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Slimware"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "slimware" ascii wide nocase
        $s2 = "pua:win32/slimware" ascii wide nocase
        $s3 = "pup.optional.slimwareutilities" ascii wide nocase
        $s4 = "slimcleaner" ascii wide nocase
        $s5 = "driverupdate.slimware" ascii wide nocase
        $s6 = "slimware.rogueware" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Slimware (Rogueware) Execution & Triage
id: eca70272-acbf-5278-b760-ea09611b5c28
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Slimware malware family. Detects suspicious execution from temporary user
  directories with hidden window flags and background transfer utilities.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/slimware
- 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.rogueware
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1189
- attack.t1204_002
- attack.t1547_001
- attack.t1053_005
- attack.t1112
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \cscript.exe
    - \wscript.exe
    CommandLine|contains:
    - AppData\Local\Temp
    - -WindowStyle Hidden
    - /e:jscript
    - bitsadmin /transfer
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: medium

rule MALWARE_WIN_SLIMWARE_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Slimware 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 = "slimware" 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. Uninstall Slimware Utilities / DriverUpdate via Windows Programs and Features.
2. Delete scheduled tasks matching 'SlimwareMaintenance' or 'DriverUpdateTask' from Windows Task Scheduler.
3. Remove startup registry entries under HKCU\Software\Microsoft\Windows\CurrentVersion\Run.
4. Run a full antimalware scan with Malwarebytes or Microsoft Defender to ensure no secondary adware remains.

What to Avoid

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

1. Do not purchase software licenses or enter payment credentials in response to unsolicited driver warning pop-ups.
2. Avoid allowing users to download unverified PC maintenance utilities from aggressive online advertisements.

References & External Analysis

• Microsoft Defender Threat Encyclopedia - PUA:Win32/Slimware Details
• Malwarebytes Labs Threat Intelligence - PUP.Optional.SlimwareUtilities
• NIST National Vulnerability Database - CVE-2015-1641
• Search "slimware" on VirusTotal (External Analysis)
• Search "slimware" on Any.Run (Sandbox Sandbox)
• Search "slimware" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Rogueware)

Explore other documented threats in the same operational category:

• Auslogics
• Tweakbit
• Winwebsec
• Safebytes

Machine-readable

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