Neshta

Overview

Neshta (cataloged across cybersecurity authorities as Virus:Win32/Neshta.A, Virus.Win32.Neshta, and Win32/Neshta) is one of the most prolific, long-standing, and disruptive polymorphic parasitic file infectors in cyber threat history. Originally written in Delphi in Belarus in 2003, Neshta infects local fixed drives and removable media by prepending its ~41,472-byte viral code to Windows 32-bit portable executable (.EXE) host files. Crucially, Neshta establishes deep operating system persistence by forcefully modifying the Windows registry command association for all executable files: it alters HKCR\exefile\shell\open\command to '%SystemRoot%\svchost.com "%1" %*'. Consequently, every time any user or system program attempts to execute any .EXE file, the infected Neshta binary runs first, scans storage drives for uninfected executables, infects them, and only then executes the original host program from a decrypted temporary file.

Known aliases

Threat reports may refer to this family under multiple names:

• Virus.Win32.Neshta
• Virus:Win32/Neshta
• Virus:Win32/Neshta.A
• W32.Neshta.A
• Win32/Neshta

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: Delphi Parasitic File Infector Engines

Known Derivatives & Downstream Variants: Neshta.A · Neshta.B · Win32/Neshta.Gen

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):

Exploited Vulnerabilities (CVEs)

This malware family is documented weaponizing the following common vulnerabilities and exposures:

• CVE-2010-2568 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).
• CVE-2012-0158 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).

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.

• 5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b
• 0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c

Delivery vectors

• Parasitic file infection spreading across removable USB media exploiting CVE-2010-2568
• Shared network folders containing prepended Trojanized utility executables

Persistence mechanisms

• HKCR\exefile\shell\open\command set to '%SystemRoot%\svchost.com "%1" %*'
• Placement of %SystemRoot%\svchost.com running before any legitimate program execution

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_NESHTA_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Neshta"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "neshta" ascii wide nocase
        $s2 = "virus.win32.neshta" ascii wide nocase
        $s3 = "virus:win32/neshta" ascii wide nocase
        $s4 = "virus:win32/neshta.a" ascii wide nocase
        $s5 = "w32.neshta.a" ascii wide nocase
        $s6 = "win32/neshta" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Neshta (File Infector) Execution & Triage
id: a090395c-b895-5265-8aa8-96a44e40897f
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Neshta 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/neshta
- 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.file-infector
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1055_002
- attack.t1547_001
- attack.t1112
- attack.t1083
- attack.t1027
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_NESHTA_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Neshta 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 = "neshta" 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 affected endpoints immediately from network shares to stop cross-machine SMB file infection.
2. Crucial: Restore the registry key HKCR\exefile\shell\open\command to '"%1" %*' before attempting to delete files, otherwise executables will fail to launch.
3. Delete the dropped viral binary located at %SystemRoot%\svchost.com.
4. Disinfect infected executables using specialized vendor removal utilities, or re-image systems from known-good golden images.

What to Avoid

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

1. Never delete %SystemRoot%\svchost.com without first fixing the exefile registry command association, as this will break executable launching across Windows.
2. Avoid executing clean binaries from mapped drives while connected to an infected workstation.

References & External Analysis

• Microsoft Defender Security Intelligence - Virus:Win32/Neshta.A
• Kaspersky Threat Intelligence - Virus.Win32.Neshta
• NIST National Vulnerability Database - CVE-2010-2568
• Search "neshta" on VirusTotal (External Analysis)
• Search "neshta" on Any.Run (Sandbox Sandbox)
• Search "neshta" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: File Infector)

Explore other documented threats in the same operational category:

• Yuner
• Coma
• Sality
• Tenga
• Sivis
• Cyn
• Pioneer
• Virut

Machine-readable

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