Killall

Overview

Executive Summary

Infection Vector and Technical Capabilities

• Security Software Neutralization: The script (often a batch file, PowerShell script, or small compiled executable) iterates through the active process list and aggressively attempts to kill processes associated with known antivirus, EDR, and logging services (e.g., `taskkill /F /IM avp.exe`).
• Database Unlocking (Ransomware Prep): In ransomware attacks, KillAll tools are used to forcibly terminate database services (SQL Server, Exchange) and enterprise applications. This releases file locks, allowing the ransomware to successfully encrypt the critical database files.
• System Instability: Extremely aggressive variants may attempt to terminate critical Windows subsystem processes, resulting in an immediate Blue Screen of Death (BSOD) or forced reboot, masking other malicious activities.

Threat Assessment

Incident Response and Remediation

• Immediate Isolation and Triage: The execution of this tool means perimeter defenses have failed and internal monitoring is compromised. Isolate the affected endpoints immediately. Assume a major payload (like ransomware) is imminent or already deploying.
• Investigate the Source: Determine how the script was executed (e.g., via a compromised RDP session, a scheduled task, or a web shell). This identifies the attacker's entry point.
• Re-enable Defenses and Re-image: Endpoints where security tools were successfully neutralized must be considered deeply compromised. A complete bare-metal wipe and re-image from a trusted baseline is required before the machine can be trusted on the network again.

Known aliases

Threat reports may refer to this family under multiple names:

• HackTool.KillAll
• Trojan.KillAV
• Script.Wiper

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_KILLALL_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Killall"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "killall" ascii wide nocase
        $s2 = "hacktool.killall" ascii wide nocase
        $s3 = "trojan.killav" ascii wide nocase
        $s4 = "script.wiper" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Killall (Ransomware) Execution & Triage
id: 4e6d9b99-8f13-5325-8713-89551575bc01
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Killall 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/killall
- 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.t1562_001
- attack.t1489
- attack.t1486
- attack.t1490
- attack.t1082
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_KILLALL_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Killall 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 = "killall" 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 affected host(s) from the internal network (disconnect physical Ethernet and disable Wi-Fi/Bluetooth) to prevent Killall from spreading laterally or encrypting network-attached storage (NAS) and shared SMB volumes.
2. Preserve volatile system memory (RAM capture) on a representative endpoint before attempting a reboot or power-down, as Killall symmetric encryption keys or uncompiled payload components may still reside in memory.
3. Audit process execution logs and terminate active scripting interpreters (e.g. PowerShell, CMD, WScript) or commands executing 'vssadmin.exe delete shadows' or 'wbadmin' used by Killall to inhibit recovery.
4. Investigate the initial compromise vector (such as exposed RDP instances, spearphishing attachments, or vulnerable edge gateways) and enforce an immediate credential reset for all compromised Active Directory accounts.
5. Restore critical assets and databases exclusively from verified, air-gapped, or immutable offline backups once the Killall binary and related persistence hooks are eradicated.

What to Avoid

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

1. Do not restart or power cycle infected systems prematurely; doing so destroys volatile RAM encryption keys and may trigger bootloader locking logic embedded in Killall.
2. Avoid negotiating or paying the extortion demand without prior forensic evaluation and consultation with incident response specialists, as payment does not guarantee data recovery.
3. Do not connect clean backup drives or external storage to the affected network until Killall eradication is completely verified.

References & External Analysis

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

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Tartober
• Huhk
• Xxyeut
• Subroate
• Cinmus
• Carrobat
• Xyligan
• Dervec

Machine-readable

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