FOR528: Ransomware for Incident Responders

Overview

The Ransomware for Incident Responders course begins with a review of ransomeware's history. We begin with the story of the first-known ransomware attack and work our way to the current-day threats that loom above our industry. Our inner-connected lives, not to mention livelihoods, are at risk everyday thanks to the advent of Human Operated Ransomware (HumOR) and Ransomware-as-a-Service (RaaS). You will better your understanding of ransomware as we deep-dive into the roles, processes, communication methods, and activities related to these threats.

After learning about the true threats we face and how we can apply IR practices in general, we begin our deep-dive into the Windows-based forensic artifacts best suited to ransomware campaign analysis. You'll learn which artifacts to collect along with which tools and methods are best suited to acquisition and parsing. Regardless of your organization's level of preparedness, we'll cover what you can do to obtain data that will facilitate analysis. You'll learn the hands-on approaches for direct acquisition against single machines and then transition to acquisition and analysis at-scale. Detailed hands-on labs walk you through analysis methods for each environment type. You'll use TimeSketch and Kibana to analyze parsed artifacts, ensuring that you recognize the easy wins and more advanced analysis practices to help you and your organization respond to the ransomware threat.

Exercises

• Install the customized FOR528 Windows and SIFT VMs, configuring them as required for detailed log review and malware analysis
• Utilize a ransomware "builder" to generate a customized ransomware encryptor payload along with a decryption tool. You will run the ransomware payload you generate, review the encrypted files, and then use the decryption tool to decrypt the data.
• Review forensic artifacts collected from a compromised environment and then parse the data using KAPE. Utilize Timeline Explorer to review data parsed via KAPE while focusing on Master File Table (MFT), System Resource Usage Monitor (SRUM), Shellbags, Shimcache, and Windows Event Log artifacts.
• Hunt data within the TimeSketch interface while focusing on how analysis of MFT, SRUM, Shellbags, Shimcache, and Windows Event Log scales when moving from manual analysis from the previous lab to at-scale analysis
• Learn the ins-and-outs of the most common interface associated with Elasticsearch, Logstash, and Kibana (ELK) stacks, Kibana, while adapting skills acquired in previous labs

Topics

• Course virtual machines

• Overview & setup

• Review of our custom target victim and their network

  • Samaran Protect see https://samaranpro.com

• Custom attack scenarios overview. Our labs and Capture the Flag are based on these atacks

• "BlueLocker" Ransomware group
• "Balrog" Ransomware group

• Ransomware evolution and history

• First-recognize ransomware attack
• Lockers and single-machine encryption payloads
• Human-Operated Ransomware (HumOR)

• Ransomware-as-a-Service (RaaS)

• RaaS model, hierarchies, and roles
• RaaS builders and generators
• RaaS dashboards

• Install Access Brokers (IABs)

• Methods of access
• Darknet marketplaces
• Victim access: Selling vs. Buying

• Ransomware operators

• Group evolution over time
• Types of extortion
• Data leak sites and psychological pressures
• Darkweb forum communications

• Forensic Artifact Collection

• Review artifacts collected by the Kroll Artifact Parser and Extractor (KAPE)
• Process/parse collected artifacts using KAPE
• Review the output of parsed artifacts to understand better the tools and methodologies leveraged to parse the forensic data for review

• Incident Response processes and their application to ransomware

• Dynamic Approach to Incident Response (DAIR) model
• Phases of a typical ransomware campaign

• Windows Forensic Artifacts

• Event Logs, Shellbags, Shimcache, SRUM, and more
• Review of the SANS Windows Forensic Analysis poster
• Using Timeline Explorer to analyze CSV files output by common parsing tools
• Artifact collection tools
• Acquiring forensic artifacts

• Analysis at scale

• Using Velociraptor to collect in bulk
• Log augmentation via Sysmon
• Log auditing review via Log-MD
• Log aggregators/SIEMs and file names

• Analysis GUIs

• TimeSketch
• Kibana

Overview

Ransomware incidents are not especially unique. We Incident Responders see the same Tactics, Techniques, and Procedures (TTPs) over and over& So let's learn how to detect them!

Section two transitions from foundational knowledge to covering the initial stages of a ransomware campaign attack cycle. We begin by covering Initial Access, Execution, Defense Evasion, and scripting engine abuse. Most ransomware cases involve actors leveraging scripting engines such as PowerShell, Batch scripts, JavaScript, Visual Basic Scripting, and more. In these early sections of the day, we discuss the various tools and scripts that we see time and time again, providing an overview of each tool along with details for hunting and detection. Next, we move to discussing Persistence. You'll learn about common Command and Control (C2) mechanisms, Remote Monitoring and Management (RMM) solutions, and native Windows methods ransomware operators use to maintain access to an environment.

Our next section focuses on attacks against Microsoft's Active Directory (AD). Ransomware operators love to attack AD, so we will break down the various ways in which they take advantage of poor AD configurations to escalate privileges and access credentials. Next we cover Privilege Escalation, Credential Access, and Lateral Movement. What tools do ransomware actors use to escalate privileges on machines? How do they access stored credentials from Windows hosts? What processes are often dumped, why, and how? For Lateral Movement you'll learn about how RDP, SMB (inc. specifically PsExec), WinRM, and other methods are used to move throughout the victim network.

Exercises

• Hunting malicious RDP activity to identify initial infection vectors and internal-to-internal lateral movement
• Identify successful phishing attacks via hunting Microsoft Office applications as parent processes, zip files opened natively in Windows, zip file credential read operations, Outlook downloading/executing files, and review of the Microsoft Trust Center
• Learn to analyze encoded and obfuscated PowerShell payloads
• Identify lateral movement via mechanisms such as RDP, PsExec, WMI, and Cobalt Strike

Topics

The phases of a ransomware attack campaign

• Initial Access
• Execution
• Defense Evasion
• Persistence
• Attacks against Active Directory
• Privilege Escalation
• Credential Access
• Lateral Movement

The following sections include in-depth details on the tools and processes noted along with methods for detection and hunting:

• Initial Access
• Top 3 IV initial access methods: RDP, Phishing, and Software Vulnerabilities
• Phishing vectors
• Malware infection vs. credential harvesting
• Malicious attachments such as MalDocs
• Review of our Email Gateway File Block List (linked)
• Malicious links and how to analyze them
• Remote Desktop Protocol (RDP)
• Import Windows Event Logs
• Identifying malicious RDP activity
• Malware-as-a-Service (Maas)

• Software exploits / Vulnerabilities

  • Zero-day vs. Common Vulnerabilities and Exposures (CVEs)
  • Example CVEs targeted and exploited in the wild
  • Darknet forum discussions RE: know vulnerabilities
• Execution and Defense Evasion
• Threat actor tooling:
• Free and Open-Source (FOSS)
• Native scripting engines
• Living Off the Land Binaries and Scripts (LOLBAS)
• Commercial tooling for adversary emulation (e.g. Cobalt Strike)
• Malware-as-a-Service (MaaS)
• Security service/mechanism bypass methods
• Native execution methods
• Windows Management Instrumentation (WMI) attacks
• Scripting engine abuse
• PowerShell
• Batch scripts
• JavaScript scripts
• Visual Basic Scripting
• PowerShell logging and advanced analysis
• Associated Windows Event Logs and enabling them
• PowerShell parameters and their purposes
• Persistence
• Common C2 methods
• Remote Monitoring and Management (RMM)
• Post-exploit frameworks (e.g. Cobaltstrike, Empire, PowerSploit, etc.)
• Account creation
• Boot / Logon auto-start locations
• Service installations
• Scheduled tasks
• WMI event subscriptions

• Active Directory (AD) Attacks

  • AD Enumeration
  • Bloodhound & SharpHound
  • Kerberoasting
  • AS-REP Roasting
  • DCSync attacks
  • Golden ticket attacks
• Privilege Escalation and Credential Access
• Commonly targeted accounts
• Methods by which accounts are targeted
• User Account Control (UAC) bypass methods
• Local Security Authority Server Service (LSASS) access and dumping
• NTDS.dit attacks
• Alternate credentials attacks
• Attacks on passwords stored in browsers and password management tools
• Session sniffers and extractors
• All-in-one solutions seen commonly (e.g. WinPwn)
• Lateral Movement
• RDP and RDP cached bitmap analysis
• Server Message Block (SMB) lateral movement
• Named pipe utilization and relation to service installs
• SysInternals PsExec
• Windows Remote Management (WinRM)
• Attacks against ESXi

Overview

Our next section focuses on attacks against Microsoft's Active Directory (AD). Ransomware operators love to attack AD, so we will break down the various ways in which they take advantage of poor AD configurations to escalate privileges and access credentials.

In section 3, we pick up where we left off in the ransomware attack lifecycle with one of the more critical sections of the course's Data Access and Data Exfiltration. Organizations usually want to know what data may have been accessed and/or stolen. We cover data archival and staging methods, including ways to hunt the tools that facilitate these activities. Would you believe that FTP is a common exfiltration route? How can you best detect data being exfiltrated, even if you don't know what data is being exfiltrated? We will show you!

We then move to the final phase of the ransomware attack, Payload deployment and the inner-workings of encryption. You willl learn about backup and recovery tampering along with the methods by which ransomware actors attack backup systems. The ways in which actors cover their tracks might seem obvious; because they are! We end this section with technical details pertaining to the most common payload deployment methods.

We then pivot to an in-depth review of Cobalt Strike (CS), an adversary emulation and attack simulation tool that has become perhaps too good at its job. Many security professionals around the world such as penetration testers and red teams rely on CS. Unfortunately, we see this extremely powerful commercial tool in a very high percentage of ransomware attacks. You will learn about the tool's infrastructure, Malleable C2 profiles, payload detection/deobfuscation methods, and more. This module includes a hands-on lab in which you will learn to decode CS payloads.

The next section covers what to do if you are about to be encrypted, are currently being encrypted, or were just recently encrypted. We cover the actions you need to take including the entities you need to contact, the departments you need to involve, and the processes you need to put in place with special attention to temporal requirements. The clock is ticking! Finally, we cover hunting methods such as identifying renamed executables, malicious files/processes via directory analysis, common attacks via anti-virus log analysis, and more. This is where we show you the best ways to keep an eye on your organization.

Exercises

• Hunt and identify data access and potential exfiltration via hunting and pivoting through NTFS metadata (NTFS, UsnJrnl, etc.), manual parsing of acquired artifacts, Timeline Explorer, TimeSketch, and Kibana
• Decoding and analysing Cobalt Strike payloads including PowerShell shellcode injectors and "stageless" beacon EXE and DLL loaders
• Detecting the threat actor's toolbox via hunting methods such as detecting PSTools, renamed executables, common directories, and more

Topics

• Data Access

• Reporting and legal considerations
• Network share enumeration and access
• Deleted file and file knowledge
• File and folder access
• Registry analysis
• Tool-specific analysis

• Data Exfiltration

• Archive creation
• Data staging
• Creation/use of .txt and .csv files
• Data exfiltration routes
• Network log and NetFlow review

• Backup and Recovery tampering

• Volume Shadow Service attacks
• Boot Configuration Data, Windows Boot Status Policy, and Windows Backup attacks
• Event log clearing

• Payload Deployment

• Common deployment tools and methods
• Deployment via PsExec
• Deployment via WMIC
• Deployment via BITS

• Encryption and Decryptors

• Encryption key types
• Overwrite vs. Copy/Delete encryption methods
• Ransom notes
• Encryption mechanism source code review
• Decryptors

• Cobalt Strike (CS)

• Threat actor access and utilization
• CS architecture and components
• Malleable C2 profiles
• Commands and cheat sheets
• Detection methods
• Payload decoding tools and methods

• Dealing with an Active Threat

  • Time considerations
  • Informed consent
  • Departments and roles that need to be involved
  • "Going Dark" a.k.a. Cutting Internet connectivity
  • Securing critical services and functions

• Ransomware Payments

• Cons regarding payment
• Pros regarding payment
• Threat actor communications and negotiations

• Hunting Ransomware Operators. Techniques to identify:

• Malicious RDP connectivity
• Process name and path anomalies
• Rogue/malicious executables
• PowerShell encoded commands
• Malicious activity in Antivirus logs
• Malicious activity involving environment variables

Overview

Nothing, and we mean nothing, can prepare you better to respond to ransomware incidents than experience. Since you do not want to gain such experience within your organization, we provide a full day Capture the Flag (CTF) Challenge that will have you analyzing ransomware incidents from the infection vector all the way through the encryption payload running within the environment. We have crafted a victim organization, Samaran Protect, to which you can most likely relate your organization. Our CTF Challenge consists of over 70 questions pertaining to a specially crafted attack scenario against our victim's organization. Our target victim's network includes 16 hosts with three VLANs:

To carry out these attacks, we devised two different ransomware groups, each of which is an amalgamation of currently operating ransomware threat groups. The Tactics, Techniques, and Procedures (TTPs) leveraged mirror real-world scenarios that those responding to ransomware events see every day. The actors involved in each scenario use different entry methods, credential access methods, tooling, deployment methods, and encryptor payloads.

Furthermore, each scenario mimics a different type of environment: One in which the victim organization does not purposefully collect forensic data to aid in incident response and one in which the victim is well-tooled and is ready for anything. Whether your organization would need to begin all artifact collection and parsing post-incident, or you have augmented your data logging and take advantage of a full-fledged SIEM, the methods we cover in our Capstone will help you relate to your organization's methods and capabilities.

Exercises

• A full day of analyzing parsed forensic artifacts and logs to answer questions common in every ransomware incident using two separate scenarios

Scenario 1: "BlueLocker" Ransomware

Scenario 2: "Balrog" Ransomware

Topics

• Digital Forensics Capstone
• Analysis
• Review parsed artifact and log data for Scenario 1 using TimeSketch
• Review parsed artifact and log data for Scenario 2 using Kibana
• Examine Windows Event logs, Sysmon data, artifacts of program execution, registry hive files, and more
• Follow the threat actor's actions from initial infection vector through encryptor payload deployment and execution
• Identify the tools, scripts, tactics, and processes used throughout each major phase of each attack campaign
• Answer the questions every organization wants answered following a ransomware event, such as:
• How did the actors get into the network?
• What data, if any, were the actors able to access?
• Were the actors able to steal (i.e. exfiltrate) any data?
• Which systems were impacted by the overall campaign, including the encryption payload itself?
• And more!