Backboot

Overview

Backboot (classified across antivirus vendors under signatures including Trojan:Win32/Backboot, Trojan:Win32/Backboot.A, and VirTool:Win32/Backboot) is a persistent Windows backdoor and low-level system manipulator. Active in multi-stage intrusion campaigns, Backboot is deployed via trojan droppers or secondary exploit stages to establish long-term persistence that survives standard system reboots and security sweeps. It targets Windows boot-time initialization routines and kernel subsystem configurations, creating deceptive system services and hook routines that intercept filesystem read and write operations. Backboot opens reverse TCP/HTTP command channels to remote C2 infrastructure, providing threat actors with interactive shell capabilities, remote file upload and download operations, and process execution capabilities while suppressing operating system security event logging.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan:Win32/Backboot
• Trojan:Win32/Backboot.A
• VirTool:Win32/Backboot
• Backdoor:Win32/Backboot
• Win32/Backboot

MITRE ATT&CK Techniques

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

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

• T1059.003: Restrict execution of Windows Command Shell (cmd.exe) and block unauthorized batch scripts.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.

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_BACKBOOT_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Backboot"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "backboot" ascii wide nocase
        $s2 = "trojan:win32/backboot" ascii wide nocase
        $s3 = "trojan:win32/backboot.a" ascii wide nocase
        $s4 = "virtool:win32/backboot" ascii wide nocase
        $s5 = "backdoor:win32/backboot" ascii wide nocase
        $s6 = "win32/backboot" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Backboot (Trojan) Execution & Triage
id: 985279a0-12f3-541a-96de-fee328e98aba
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Backboot 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/backboot
- https://malware-families-catalog.systemhelpdesk.com/defensive/downloader-dropper-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.trojan
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1542_003
- attack.t1059_003
- attack.t1543_003
- attack.t1562_001
- attack.t1071_001
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_BACKBOOT_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Backboot 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 = "backboot" 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. Sever network connections immediately to prevent unauthorized remote command execution.
2. Inspect system services using sc.exe or PowerShell to identify rogue services registered in HKLM\SYSTEM\CurrentControlSet\Services.
3. Verify boot sector and BCD store integrity using bootrec.exe /fixmbr and bcdedit.
4. Terminate malicious service hosts and delete corresponding binary files from System32 or Drivers directories.
5. Scan the entire disk with an offline rescue media antimalware scanner to ensure rootkit/bootkit components are purged.

What to Avoid

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

1. Do not perform standard in-OS remediation without checking offline registry and boot records, as kernel hooks may mask files.
2. Do not reboot into standard Windows mode before verifying rogue persistence mechanisms are disabled.

References & External Analysis

• Microsoft Defender Threat Encyclopedia - Trojan:Win32/Backboot
• Trend Micro Threat Encyclopedia - Backdoor.Win32.Backboot
• Kaspersky Threat Intelligence Portal - Trojan.Win32.Backboot
• Search "backboot" on VirusTotal (External Analysis)
• Search "backboot" on Any.Run (Sandbox Sandbox)
• Search "backboot" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Ursu
• Hmgfa45Id4O
• Zamg
• Maplestory
• Cookiesstealer
• Vbclone
• Mepaow
• Dnschanger

Machine-readable

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