Hackav

Overview

Trojan:Win32/Hackav is a specific classification for utility malware designed with a singular, critical purpose: to impair, terminate, or completely uninstall legitimate endpoint security software (Antivirus, EDR, and Windows Defender). Hackav tools are almost never used in isolation; they are deployed by attackers as a precursor step immediately before executing a highly destructive payload, most commonly ransomware, to ensure the encryption process goes uninterrupted (`T1562.001`).

Understanding Hackav (AV Killers)
To an end-user, Hackav is invisible, though they might briefly notice a Windows notification stating that their antivirus has been turned off. For a security operations center, the execution of Hackav is a 'Code Red' alarm. It means an attacker has achieved high-level administrative privileges and is actively clearing the way for a catastrophic attack.

Execution and Impairment Mechanics
Hackav requires administrative or SYSTEM privileges to function. Once deployed by an affiliate or initial access broker, it employs extremely aggressive techniques. It may use legitimate, signed drivers (Bring Your Own Vulnerable Driver - BYOVD) (`T1068`) to gain kernel-level access to forcefully terminate protected EDR processes. It modifies the Windows Registry (`HKLM\SOFTWARE\Policies\Microsoft\Windows Defender`) to permanently disable real-time protection. It may also attempt to uninstall security software using silent WMI commands or by stopping critical security services (`T1562.001`).

Indicators of Compromise & Impact
The primary impact is the complete loss of endpoint visibility and protection, invariably followed by a major secondary attack. Host-based IoCs include EDR alerts (often the final alert before the agent goes offline) indicating tampering, unexpected stopping of security services (e.g., `WinDefend`), and unauthorized registry modifications targeting AV policies. The presence of known vulnerable drivers (like `procexp.sys` or outdated hardware drivers) dropped in the `%Temp%` directory is a major warning sign.

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_HACKAV_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Hackav"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "hackav" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Hackav (Ransomware) Execution & Triage
id: 7597b222-e162-5c72-bfc0-0e1afcf24d11
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Hackav 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/hackav
- 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.t1486
- attack.t1068
- attack.t1562_001
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_HACKAV_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Hackav 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 = "hackav" 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. Isolate the endpoint IMMEDIATELY at the network switch level. If Hackav has run successfully, ransomware execution is likely imminent.
2. Investigate how the attacker gained the administrative privileges necessary to run the AV killer (e.g., compromised credentials, local privilege escalation).
3. Hunt across the environment for the specific Hackav executable or the vulnerable drivers it dropped, as the attacker may be preparing multiple machines.
4. Do not rely on the local AV for cleanup, as it has been compromised; use a standalone, bootable forensic tool or reinstall the OS.

What to Avoid

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

1. Do not assume it's a false positive if an endpoint suddenly stops reporting to the EDR console; treat it as a critical incident.
2. Avoid turning the machine off entirely if possible, as capturing a memory image is vital for analyzing the follow-on payload.

References & External Analysis

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

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Xxyheo
• Pcclean
• Genericrxex
• Genericrxax
• Kryptstarter
• Retribution
• Itva
• Bplug

Machine-readable

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