T1135: Network Share Discovery

Framework: MITRE ATT&CK · Tactic: Discovery · Total Cataloged Families: 2 · Observed Samples: 1 · Primary Threat Categories: Ransomware · Trojan

Operational Executive Summary

T1135 (Network Share Discovery) is classified under the Discovery tactic within the MITRE ATT&CK framework. Techniques adversaries employ to observe and orient themselves within an enterprise environment, profiling network shares, Active Directory domains, and local system configurations. In telemetry gathered across enterprise endpoints and the EMBER 2018 benchmark, this technique was weaponized across 2 distinct malware families, totaling over 1 validated samples.

Technical Anatomy & Adversary Tradecraft

Adversaries leverage Network Share Discovery to accomplish operational objectives while minimizing anomalous forensic footprints. When executing Network Share Discovery, malicious binaries commonly interact directly with low-level Windows APIs, kernel mode drivers, or native scripting interfaces to bypass traditional file-integrity monitors and static antivirus signatures.

In modern multi-stage campaigns, T1135 is frequently observed functioning as an intermediate bridge: initial access payloads (such as spearphishing loaders or exploit macros) execute Network Share Discovery to establish in-memory execution or persistence before staging secondary ransomware or data-exfiltration implants.

Authoritative MITRE ATT&CK Reference: View official technique documentation, sub-techniques, and adversary groups at https://attack.mitre.org/techniques/T1135/.

Detection Engineering & Threat Hunting

Detecting Network Share Discovery requires telemetry correlation across endpoint detection and response (EDR) agents, Sysmon event streams, and security information event management (SIEM) pipelines:

Process Creation & Lineage: Monitor parent-child process anomalies where unexpected parent binaries (e.g., Office executables, web browsers, or script hosts) spawn command shells or native Windows utilities.
API Hooking & Behavioral Telemetry: EDR platforms should flag rapid calls to memory allocation, process injection, or registry manipulation APIs originating from unbacked executable memory regions.
Network Anomaly Correlation: Cross-reference endpoint execution timestamps with external network socket establishment to identify anomalous beaconing or covert data staging.

SOC Containment & Hardening Guidance

To mitigate risks associated with T1135 (Network Share Discovery) across production infrastructure, security teams should implement the following defensive controls:

Attack Surface Reduction (ASR): Enforce strict application control policies (WDAC or AppLocker) to restrict execution to signed and verified corporate binaries.
Least Privilege & Credential Hygiene: Restrict local administrative privileges to prevent adversaries from tampering with defensive agents or escalating privileges.
Network Microsegmentation: Restrict lateral communication across endpoint VLANs to prevent wormable payloads from utilizing Network Share Discovery across adjacent network segments.

→ Incident Response Guidance: Read our Active Incident Response Playbook

Cataloged Malware Families Utilizing T1135 (2 Families)

The following malware families in the SystemHelpDesk catalog have been verified utilizing T1135 (Network Share Discovery):

2 families

Family	Category	Sample Count	Technical Summary
fspm	Ransomware	`1`	<h3>Executive Summary</h3> Fspm is a classification typically applied to a HackTool or localized exploit script designed to bypass security controls or facilita...
lanfiltrator	Trojan	`Sampled`	LanFiltrator (cataloged across security software as Trojan:Win32/LanFiltrator, Spyware.Win32.LanFiltrator, and Trojan.LanFiltrator) is a specialized local area ...