New SMB Executable File Transfer Activity

Risk Factors

When a server receives an unusual file type, particularly an executable file, there is a risk that the file is malware. Once uploaded to a file share, malware can easily propagate to other devices on your network.

Background

After an attacker compromises a workstation, the attacker searches for new targets on the network. Malware can be installed on victims by transferring files with these executable file extensions: .exe, .bat, .dll, or .ps1. If the compromised workstation has credentials that provide the attacker with administrative access to a new target, the attacker can transfer the executable file to a restricted file share such as ADMIN$ or C$. After the malicious payload from the file runs through the actions of the attacker or the victim, the attacker can install malware that enables them to move laterally to the newly compromised device.

Mitigation Options

Restrict file share access to only authorized IP addresses and users

Disable anonymous (null) file share access

Restrict file share authentication with a password

MITRE ATT&CK ID

Associated content

Announcing The Forrester Wave™: Network Analysis And Visibility Solutions, Q4 2025

Network analysis and visibility solutions remain underrepresented in enterprises. Find out why in this preview of a new Wave report.

Report

Learn more

ExtraHop® Named a Leader in First-Ever Gartner® Magic Quadrant™ for Network Detection and Response — ExtraHop

ExtraHop® Named a Leader in First-Ever Gartner® Magic Quadrant™ for Network Detection and Response

News

Learn more

Detections

Visit this resource for more information.

Documentation

Learn more

The 2025 ExtraHop Global Threat Landscape Report: The Alarming Reality of Threat Actor Dwell Time and Deeper Network Access — ExtraHop

This analysis exposes the critical link between an organization's lack of internal visibility and the escalating cost of compromise, demanding an urgent re-evaluation of how core business assets are protected.

Blog Post

Learn more

ExtraHop RevealX MITRE ATT&CK Coverage 2024 — ExtraHop

Learn why you need to be wary of the claims certain network detection and response providers make about their coverage against the MITRE ATT&CK framework.

Blog Post

Learn more

MITRE ATT&CK - Network Detection & Response with RevealX — ExtraHop

Learn how NDR from RevealX helps security teams detect and investigate more adversary TTPs in the MITRE ATT&CK framework than rule-based tools.

External

Learn more

What else can RevealX do for you?

View our Periodic Table of use cases