This incident is only detected if you have integrated Microsoft Entra ID with Lumu. Check out our Microsoft Entra ID Out-of-the-Box integration guide for more information.

The Lumu Anonymized Login Incident Response Playbook is based on the Computer Security Incident Handling Guide by the National Institute of Standards and Technology (NIST). According to NIST special publication 800-61, the incident response life cycle has four main phases, as described in the following illustration.

Based on the source: NIST special publication 800-61

This document contains guidelines for Anonymized Login incident response using Lumu. Consider this playbook as a guideline to improve the effectiveness of the incident response and adapt it according to your specific requirements.

What are Anonymized Login incidents?

Through its integration with Microsoft Entra ID, Lumu actively monitors Active Directory user data and authentication telemetry. When an account within the active directory authenticates from anonymized infrastructure, Lumu detects the concealed IP and alerts the incident.

Anonymized Login incidents serve as an indicator that a user account has successfully authenticated using an IP concealer. Lumu detects connections from Virtual Private Networks (VPNs), proxy servers, or the TOR network.

Even though your organization’s users can use VPNs and proxy servers for legitimate purposes, such as remote work, threat actors heavily rely on these tools to orchestrate attacks as it will allow them to perform damaging activities without exposing their actual Command-and-Control (C2) infrastructure and geolocation.

Anonymized login is not an isolated event, it indicates compromised credentials and the entry point for a broader attack sequence. Attackers usually use this method to:

• Move laterally within the organization: Once an attacker establishes an initial foothold using an anonymized login, they use this connection to blend in with normal network traffic. They leverage the compromised identity to move laterally across the network—accessing internal file shares, mapping network drives, or launching Remote Desktop Protocol (RDP) sessions
• Escalate privileges: Attackers can probe the Active Directory environment to execute attacks against Domain Controllers, scrape memory for credential hashes, or exploit misconfigurations to elevate their privileges to affect systems with higher clearance.

General Playbook

This is the general playbook for Anonymized Login incident operation. It covers the main steps that you can take when investigating and remediating this type of incident.

Example Scenario

Now, let’s delve into a common scenario that an organization can find when operating Anonymized Login incidents. This will help exemplify the value this feature can provide. Let’s consider a scenario where Lumu notifies your organization that one of your AD accounts has logged in using a VPN.

1. Organization A gets notified of an Anonymized Login for the user Jane Doe. From the Lumu Portal, the analysts inspect the information provided in the incident and notice several connections from a VPN. Before proceeding with any action the analysts start drilling down the data to define the course of action.

2. After reviewing the policies of the company, the analyst notices that the connection was done through an unauthorized VPN.

If the connection was made through TOR, that is a clear indicator of an attack to your organization infrastructure and it is recommended to take immediate action.

3. To confidently determine this is an attack or a legitimate connection, the analyst starts drilling down the data provided in the Lumu Portal. The analyst reviews the context of the obfuscated login and compares it with the users previous 10 sessions to determine a base line of behavior.

4. After the review of the incident, the analyst notices several red flags:

• This connection was made from Firefox, which has only been used for this login.
• The account has logged in from an unmanaged device when all the other connections were made through a managed device.
• The user accessed Azure, which she hadn’t before and for her role it is very unlikely that she requires to do any operation there.

5. Having established that the context of the login highly deviates from the normal user behavior, the analyst contacts the user to make sure that this is an illegitimate connection.

6. After contacting the user, the analyst confirms this is an account takeover. The analyst immediately disables Jane Doe's account in Entra ID and revokes all active sign-in sessions to contain the threat.

Before disabling any account, the analyst must verify its role and privileges. If the compromised identity is a critical administrative account or service account tied to your organization’s processes, abruptly blocking it could disrupt essential business operations. For those cases, implement alternative containment measures—such as immediate password rotation, enforcing strict location-based Conditional Access, or isolating the affected applications—to neutralize the threat without breaking operability.

7. Having contained the immediate threat, the analyst starts the investigation of the incident to determine the scope and reach of the attack. Using the Recent Log Activity section of the incident details, the analyst is able to review the high risk changes made in the account during the attack.

8. Then, the analyst uses Lumu Discover to determine how the attacker got the credentials to access the account. After reviewing the organization’s compromised employees, the analyst notices that the user was involved in an infostealer incident.

9. Once the scope and the root cause of the attack is determined, the analyst proceeds with an account reset and enforces new muti-factor authentication policies. The device is also taken in to erase the infostealer malware making sure the device’s health matches the organization standards.

Preparation

This is the initial phase where organizations take preventive measures to respond effectively to incidents, some recommended steps to prepare your company to deal with a Anonymized Login incident are listed below:

• Incident Handler Communications and Facilities: It’s vital to gather contact information of everyone involved with incident response to facilitate contact during an incident. Compilate contact information of incident response (IR) team members, external IR teams, and eventually law enforcement, with primary and backup contacts. Determine the escalation and de-escalation criteria and incident reporting mechanisms, such as phone numbers, email addresses, and secure instant messaging.
• Roles and Responsibilities: Details of the roles and responsibilities of key individuals and teams responsible for incident response and decision-making should also be gathered at this stage.
• Training and awareness: Train the incident response (IR) team to identify common MITRE ATT&CK techniques used by adversaries that involve logging in to corporate accounts to damage the organization, and study possible mitigations:
  • ID T1090.002 - External Proxy: Adversaries may use an external proxy to act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure. Adversaries may use these types of proxies to manage command and control communications, reduce the number of simultaneous outbound network connections, provide resiliency in the face of connection loss, or to ride over existing trusted communications paths between victims to avoid suspicion.
  • ID T1090.003 - Multi-hop Proxy: To disguise the source of malicious traffic, adversaries may chain together multiple proxies. Typically, a defender will be able to identify the last proxy traffic traversed before it enters their network; the defender may or may not be able to identify any previous proxies before the last-hop proxy. This technique makes identifying the original source of the malicious traffic even more difficult by requiring the defender to trace malicious traffic through several proxies to identify its source.
  • ID T1078.004 - Cloud accounts: Adversaries may obtain and abuse credentials of a cloud account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials for cloud accounts can be used to harvest sensitive data from online storage accounts and databases.

How Lumu Helps

Lumu provides the ability to illuminate the blind spots in your network by providing coverage of your entire infrastructure, namely on-premises, public and private clouds, and roaming devices.

Recommended Actions

• To gain full visibility into your network, set up collectors such as Virtual Appliances, Gateways, Agents and integrations to ensure that all your network metadata is ingested in the Lumu platform, especially the firewall and proxy metadata. Learn more in our deployment guide.
• Ensure you cover remote users in your compromise assessment. Learn more about Lumu Agent and VPN and SDP configuration.
• Identify your vital assets (clients, IoT, clouds, remote devices, etc.) and assign labels to your traffic to help quickly identify the compromise distribution across your infrastructure in a way that makes sense for your organization.
• Control your attack surface by ensuring that services and connections exposed to external environments are governed by strict policies and controls. Verify that only essential services are exposed, and access is restricted to specific roles via secure, authenticated channels. Regularly monitor and enforce these measures to minimize vulnerabilities.
• Conduct regular awareness campaigns on security policies and risks employees face, and what actions to take when faced with a cyberattack.
• Keep your endpoint protection and operating systems updated.
• Implement best practices for Identity and Access Management (IAM).

Detection & Analysis

Organizations should prioritize rapid incident detection and validation to enable effective containment and eradication. Early detection limits the spread of infection and simplifies the response process. During this phase, security teams monitor and analyze alerts and data from systems, networks, and logs to identify potential incidents, understand the threat's scope, impact, and potential source, assess its severity, and gather forensic information. Proper documentation and communication are essential for successful incident response.

Some steps are listed below:

• Alert Monitoring: Collect and monitor data from network, host, and application logs, along with external sources like threat intelligence, to identify attack vectors and signs of potential incidents.
• Incident Identification: Determine whether an event qualifies as an incident or precursor by analyzing and correlating monitoring data.
• Incident Analysis: Classifying the incident type, incident response teams should quickly analyze and validate incidents. Once an incident is confirmed, the team conducts an initial analysis to determine its scope, including affected systems, origin, and attack methods. This analysis helps prioritize actions like containment and deeper investigation.
• Enrichment and Investigation: Gathering additional information (e.g., threat intelligence, forensics analysis) to understand the scope and impact. Maltiverse by Lumu is vital in this procedure.
• Documentation: Recording the details of the incident, timelines, and results of the analysis. An IR team that suspects an incident has occurred should immediately begin recording all facts related to the incident.

How Lumu Helps

Lumu unlocks the value of your own network metadata by implementing the concept of Continuous Compromise Assessment that provides comprehensive and detailed visibility into your network infrastructure. Lumu illuminates the various activities associated with indicators of compromise (IoCs) detected on your network and provides all the contextual information needed for in-depth analysis through the Lumu Portal.

1. Lumu Continuous Compromise Assessment technology provides real-time monitoring over network and identity infrastructure. It correlates network and identity metadata to identify anomalies and contact with malicious infrastructure, providing your organization with multiple tools to determine adverse activity.
   
2. Through Lumu’s out-of-the-box integrations, you can directly integrate Microsoft Entra ID with Lumu’s detection capabilities to monitor suspicious behaviour in your organization’s accounts.
   
3. Use Lumu Discover to monitor and control your organization’s exposed attack surface, while letting you monitor compromised employees, data leaks, and infostealers that have affected your organization’s domain
   
4. Use the IoC information provided by Lumu to check if the log files of your defensive infrastructure (e.g. endpoint protection, firewall, UTM gateway) contain this malicious communication.
   
5. Identify the endpoints contacting the adversarial infrastructure related to Anonymized Login incidents. This can be IoCs related to brute force, scanning infrastructure or ransomware gangs.
   
6. Use the Attack Distribution feature of the Lumu Portal to see how the compromise spreads inside your network. Identify how your assets are communicating with the adversarial infrastructure and detect endpoints within the internal network exhibiting anomalous behavior.
   
7. You can use the Lumu’s Compromise Radar feature to find out the frequency and behavior of malicious communication, so you can differentiate occasional contact from persistent and automated compromises that have the power to cause harm to the organization.
   
8. Use the threat intelligence information provided in each IOC in the Lumu Portal to enrich the context of the activity. Additionally, correlate this with other detections, like Unusual Login, to verify whether the attack attempts were successful.
   
9. If an incident is confirmed, use this information in incident documentation and analysis.
   
10. If possible, reverse-engineer the malware in a secure environment (or sandbox) to understand its behavior and the functionality it implements.
    

Containment, Eradication & Recovery

This phase has two key goals: stopping the spread of the threat and preventing further damage within the network. Organizations should implement strategies and procedures based on the risk level of the detected compromise. Containment strategies will vary depending on the type of incident and must consider potential damage or theft of resources, the need for evidence preservation, service availability, and the time and resources required for effective response.

Below are some steps to follow in this phase:

• Containment: Implement immediate actions or long-term strategies to isolate or limit the spread of the incident.
• Eradication: Identify the root cause of the incident and eliminate it.
• Recovery: Recover affected systems to a known good state and confirm normal operations, perform testing to ensure systems are no longer compromised, and prevent future incidents.

How Lumu Helps

Confirmed compromise intelligence about the compromised device helps security analysts to understand where and how to contain and eradicate the compromise.

Recommended Actions

• Lumu Defender integrates with your security stack and gives your organization the ability to orchestrate an effective automated response to contain any cyber threat, in line with your policies.
• Lumu orchestration can assist you in identifying whether the endpoints that reported the Anonymized Login were observed displaying anomalous behavior before.
• Use the threat Intelligence information, Mitre ATT&CK TTPs, and IoCs details from Lumu Portal to configure your security infrastructure scheme (firewalls, IDS, IPS, email gateways, etc) to avoid similar malicious activity.
• Lumu Portal provides your organization with information and details about the devices or IP addresses involved in the incident to initiate targeted investigations into the related internal devices.
• Based on your containment strategy, consider isolating the affected devices to prevent lateral movement and limit the spread of the incident within the network
• Identify related services and users and reset the credentials of all involved systems.
• If you suspect the initial attack vector was via email, check the details in the organization's mail server log files.
• Remove threats, and replace or restore the compromised assets to their previous state. Wipe and baseline affected systems if needed.
• Use Lumu technology to establish monitoring to detect further suspicious activity.
• The incident and its effects need to be remediated across the entire network.
• Complete malware scanning of all systems across the affected network.

Post-Incident Activity

This phase is designed to incorporate the lessons learned from each incident and to evaluate future improvements.

• Lessons Learned: Conduct post-incident reviews to analyze the incident and determine areas for improvement. This step should answer at least the next key questions:
  • What were the root causes of the incident and the incident response issues?
  • Could the incident have been prevented? How?
  • What went well in the incident response?
  • How can we improve our response to future incidents?
• Incident Reporting: Document the incident and share reports with necessary stakeholders.
• Process Improvement: Update policies, procedures, and tools based on findings from the incident.

How Lumu Helps

Lumu helps refine your current and future defense and response by continuously monitoring that the compromise has been eradicated.

Recommended Actions

• Use Lumu Continuous Compromise Assessment to monitor continuously any communication between your assets and adversarial infrastructure to make sure that no additional contacts are reported.
• Use the context information in the Lumu Portal for details on how the adversary works.
• Conduct root cause analysis and evaluate the habits of the users.
• Explore the related sources, Mitre ATT&CK Matrix, and articles provided by Lumu in the Context area to understand more about the Tactics, Techniques and Procedures used by adversaries and document the incident.
• Use the incident information to adjust your security policies and Mitre Matrix context to evaluate your security strategy. This may involve changing the configuration of the company's assets and conducting awareness campaigns, focusing on the users that own those devices.
• Coordinate with your endpoint protection technology vendor’s updates if needed.
• Document and share with the stakeholders all the lessons learned from the incident and recommendations of any aspect that could be improved to help prevent a similar cyber incident from reoccurring.