Cyber Threat Report: 'Threat Assessment: Black Basta Ransomware'

This threat assessment from Palo Alto's Unit 42 describes the Black Basta 'Ransomware as a Service' operation including TTPs (tactics, techniques and procedures) and technical details about the ransomware. The authors also describe recommended courses of action to prevent and detect the threat.

Restrict Registry Permissions

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

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...

Restrict File and Directory Permissions

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

User Account Management

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

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.

Privileged Account Management

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

Exploit Protection

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

SSL/TLS Inspection

Break and inspect SSL/TLS sessions to look at encrypted web traffic for adversary activity.

Network Intrusion Prevention

Use intrusion detection signatures to block traffic at network boundaries.

Data Backup

Take and store data backups from end user systems and critical servers. Ensure backup and storage systems are hardened and kept separate from the corporate network to prevent compromise.

Execution Prevention

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

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.

Multi-factor Authentication

Use two or more pieces of evidence to authenticate to a system; such as username and password in addition to a token from a physical smart card or token generator.

Restrict Web-Based Content

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

Software Configuration

Implement configuration changes to software (other than the operating system) to mitigate security risks associated to how the software operates.

Antivirus/Antimalware

Use signatures or heuristics to detect malicious software.

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.

Code Signing

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

Audit

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

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.

Password Policies

Set and enforce secure password policies for accounts.

Disable or Remove Feature or Program

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

Restrict Library Loading

Prevent abuse of library loading mechanisms in the operating system and software to load untrusted code by configuring appropriate library loading mechanisms and investigating potential vulnerable software.

Data Loss Prevention

Use a data loss prevention (DLP) strategy to categorize sensitive data, identify data formats indicative of personal identifiable information (PII), and restrict exfiltration of sensitive data.(Citation: PurpleSec Data Loss Prevention)

Limit Access to Resource Over Network

Prevent access to file shares, remote access to systems, unnecessary services. Mechanisms to limit access may include use of network concentrators, RDP gateways, etc.