S0457: Netwalker

S0457: Netwalker describes [Netwalker](https://attack.mitre.org/software/S0457) is fileless ransomware written in PowerShell and executed directly in memory.(Citation: TrendMicro Netwalker May 2020)

Executive priority

S0457: Netwalker is an official MITRE ATT&CK software. Glexia treats it as defensive behavior context for prioritizing monitoring, control validation, and response planning without using the object by itself as an attribution claim.

Technical view

Security teams should validate S0457: Netwalker by reviewing the official ATT&CK relationships, mapped tactics (the mapped ATT&CK tactic context), supported platforms (Windows), and available local telemetry before making detection or mitigation decisions.

Likely telemetry

Official ATT&CK relationships and object metadata
Network, endpoint, and security-tool telemetry

Detection direction

Validate whether S0457: Netwalker appears in your detection coverage and tabletop scenarios.
Use the object to align executive risk language with SOC, incident response, and detection engineering work.
Do not treat ATT&CK relationship context as attribution without corroborating evidence.

Mitigation priorities

Map the object to existing controls and identify missing telemetry or response ownership.
Prioritize mitigations that reduce exposure on the listed platforms and tactics.
Review adjacent ATT&CK relationships before changing policy, detections, or reporting language.

Additional notes and limits

Baseline Glexia take generated from the official MITRE ATT&CK STIX object, source hash, tactics, platforms, and detection fields. It is safe to replace with a richer model-generated take for the same source hash later.

This baseline take is source-grounded and schema-validated, but it does not include environment-specific telemetry, incident evidence, or threat-intelligence corroboration.

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Official MITRE ATT&CK definition

Netwalker

Netwalker is fileless ransomware written in PowerShell and executed directly in memory.[1]

View the same entry on attack.mitre.org (MITRE-hosted reference; in-page links above use the Glexia ATT&CK library.)

Glexia analysis

How security teams should use this page

Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.

ATT&CK relationship table

Techniques used

This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.

Filter related techniques18 rows

Domain	ID	Name	Relationship / procedure
Enterprise	T1112	Modify Registry	Netwalker can add the following registry entry: `HKEY_CURRENT_USER\SOFTWARE\{8 random characters}`.[1]
Enterprise	T1685	Disable or Modify Tools	Netwalker can detect and terminate active security software-related processes on infected systems.[1]CitationSophos Netwalker May 2020
Enterprise	T1082	System Information Discovery	Netwalker can determine the system architecture it is running on to choose which version of the DLL to use.[1]
Enterprise	T1570	Lateral Tool Transfer	Operators deploying Netwalker have used psexec to copy the Netwalker payload across accessible systems.CitationSophos Netwalker May 2020
Enterprise	T1140	Deobfuscate/Decode Files or Information	Netwalker's PowerShell script can decode and decrypt multiple layers of obfuscation, leading to the Netwalker DLL being loaded into memory.CitationSophos Netwalker May 2020
Enterprise	T1059.003	Windows Command ShellSub-technique	Operators deploying Netwalker have used batch scripts to retrieve the Netwalker payload.CitationSophos Netwalker May 2020
Enterprise	T1027.010	Command ObfuscationSub-technique	Netwalker's PowerShell script has been obfuscated with multiple layers including base64 and hexadecimal encoding and XOR-encryption, as well as obfuscated PowerShell functions and variables.[1]CitationSophos Netwalker May 2020
Enterprise	T1518.001	Security Software DiscoverySub-technique	Netwalker can detect and terminate active security software-related processes on infected systems.[1]
Enterprise	T1027.009	Embedded PayloadsSub-technique	Netwalker's DLL has been embedded within the PowerShell script in hex format.[1]
Enterprise	T1490	Inhibit System Recovery	Netwalker can delete the infected system's Shadow Volumes to prevent recovery.[1]CitationSophos Netwalker May 2020
Enterprise	T1059.001	PowerShellSub-technique	Netwalker has been written in PowerShell and executed directly in memory, avoiding detection.[1]CitationSophos Netwalker May 2020
Enterprise	T1106	Native API	Netwalker can use Windows API functions to inject the ransomware DLL.[1]
Enterprise	T1486	Data Encrypted for Impact	Netwalker can encrypt files on infected machines to extort victims.[1]
Enterprise	T1569.002	Service ExecutionSub-technique	Operators deploying Netwalker have used psexec and certutil to retrieve the Netwalker payload.CitationSophos Netwalker May 2020
Enterprise	T1047	Windows Management Instrumentation	Netwalker can use WMI to delete Shadow Volumes.[1]
Enterprise	T1489	Service Stop	Netwalker can terminate system processes and services, some of which relate to backup software.[1]
Enterprise	T1105	Ingress Tool Transfer	Operators deploying Netwalker have used psexec and certutil to retrieve the Netwalker payload.CitationSophos Netwalker May 2020
Enterprise	T1055.001	Dynamic-link Library InjectionSub-technique	The Netwalker DLL has been injected reflectively into the memory of a legitimate running process.[1]

Relationship explorer

All related ATT&CK context

Change history

Object version and sync metadata

The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.

ATT&CK release: 19.2
Object version: 1.1
Created: May 26, 2020, 21:02 UTC (UTC+00:00)
Modified: Apr 16, 2025, 20:38 UTC (UTC+00:00)
Raw hash: eaea9820bbf91bab...

Imported snapshots across ATT&CK releases(2)

Release	Bundle imported	Object version	Modified	Status	Raw hash
19.2	Aug 6, 2026, 02:58 UTC (UTC+00:00)	1.1	Apr 16, 2025, 20:38 UTC (UTC+00:00)	Current bundle	`eaea9820bbf9…`
19.1	Jul 14, 2026, 09:14 UTC (UTC+00:00)	1.1	Apr 16, 2025, 20:38 UTC (UTC+00:00)	Older bundle	`eaea9820bbf9…`

Raw source

Mirrored ATT&CK source object

The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.

Open mirrored raw JSON Open MITRE-hosted copy

Source references

External references and citations

MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.

[1]
TrendMicro Netwalker May 2020
Victor, K.. (2020, May 18). Netwalker Fileless Ransomware Injected via Reflective Loading . Retrieved May 26, 2020.
Open source URL
[2]
mitre-attackS0457
Open source URL

Source and licensing

Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.

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