Cyber Threat Report: 'Flax Typhoon using legitimate software to quietly access Taiwanese organizations'

This blog post by Microsoft Threat Intelligence outlines the Flax Typhoon intrusion set and TTPs demonstrated by the group. It describes the actor as a nation-state group based in China which has been observed targeting dozens of organizations in Taiwan. The post outlines the tools and techniques used by the group. The researchers assess the groups motivation to be espionage. It also outlines how to defend against Flax Typhoon attacks, providing indicators of compromise to help detect associated activity.

Restrict File and Directory Permissions

Restrict access by setting directory and file permissions that are not specific to users or privileged accounts.

Execution Prevention

Block execution of code on a system through application control, and/or script blocking.

User Training

Train users to be aware of access or manipulation attempts by an adversary to reduce the risk of successful spearphishing, social engineering, and other techniques that involve user interaction.

Behavior Prevention on Endpoint

Use capabilities to prevent suspicious behavior patterns from occurring on endpoint systems. This could include suspicious process, file, API call, etc. behavior.

Antivirus/Antimalware

Use signatures or heuristics to detect malicious software.

Code Signing

Enforce binary and application integrity with digital signature verification to prevent untrusted code from executing.

Privileged Account Management

Manage the creation, modification, use, and permissions associated to privileged accounts, including SYSTEM and root.

Restrict Web-Based Content

Restrict use of certain websites, block downloads/attachments, block Javascript, restrict browser extensions, etc.

Disable or Remove Feature or Program

Remove or deny access to unnecessary and potentially vulnerable software to prevent abuse by adversaries.

User Account Management

Manage the creation, modification, use, and permissions associated to user accounts.

Limit Software Installation

Block users or groups from installing unapproved software.

Audit

Perform audits or scans of systems, permissions, insecure software, insecure configurations, etc. to identify potential weaknesses.

Operating System Configuration

Make configuration changes related to the operating system or a common feature of the operating system that result in system hardening against techniques.

Filter Network Traffic

Use network appliances to filter ingress or egress traffic and perform protocol-based filtering. Configure software on endpoints to filter network traffic.

Network Intrusion Prevention

Use intrusion detection signatures to block traffic at network boundaries.

Privileged Process Integrity

Protect processes with high privileges that can be used to interact with critical system components through use of protected process light, anti-process injection defenses, or other process integrity enforcement measures.

Password Policies

Set and enforce secure password policies for accounts.

Active Directory Configuration

Configure Active Directory to prevent use of certain techniques; use SID Filtering, etc.

Encrypt Sensitive Information

Protect sensitive information with strong encryption.

Credential Access Protection

Use capabilities to prevent successful credential access by adversaries; including blocking forms of credential dumping.

Restrict Registry Permissions

Restrict the ability to modify certain hives or keys in the Windows Registry.

Application Isolation and Sandboxing

Restrict execution of code to a virtual environment on or in transit to an endpoint system.

Exploit Protection

Use capabilities to detect and block conditions that may lead to or be indicative of a software exploit occurring.

Vulnerability Scanning

Vulnerability scanning is used to find potentially exploitable software vulnerabilities to remediate them.

Update Software

Perform regular software updates to mitigate exploitation risk.

Network Segmentation

Architect sections of the network to isolate critical systems, functions, or resources. Use physical and logical segmentation to prevent access to potentially sensitive systems and information. Use a DMZ to contain any internet-facing services...