XDR-Analyst Palo Alto Networks XDR Analyst Questions and Answers

A BIOC rule is a custom detection rule that uses the Cortex Query Language (XQL) to define the behavior or actions that indicate a potential threat. A BIOC rule can use the xdr_data and cloud_audit_log datasets and presets for these datasets. A BIOC rule can also use the filter stage, alter stage, and functions without any aggregations in the XQL query. The query must return a single field named action_process_image, which is the process image name of the suspicious process. The query must also include the event_type and event_sub_type fields in the filter stage to specify the type and sub-type of the event that triggers the rule.

Option B is the correct answer because it meets all the requirements for a valid BIOC rule query. It uses the xdr_data dataset, the filter stage, the event_type and event_sub_type fields, and the action_process_image_name field with a regular expression to match any process image name that ends with .pdf.exe or .docx.exe, which are common indicators of malicious files.

Option A is incorrect because it does not include the event_type field in the filter stage, which is mandatory for a BIOC rule query.

Option C is incorrect because it does not include the event_type and event_sub_type fields in the filter stage, and it uses the fields stage, which is not supported for a BIOC rule query. It also returns the action_process_image field instead of the action_process_image_name field, which is the expected output for a BIOC rule query.

Option D is incorrect because it uses the event_behavior field, which is not supported for a BIOC rule query. It also does not include the event_type field in the filter stage, and it uses the event_sub_type field incorrectly. The event_sub_type field should be equal to PROCESS_START, not true.

The type of BIOC rule that is currently available in Cortex XDR is Discovery. A Discovery BIOC rule is a rule that detects suspicious or malicious behavior on endpoints based on the Cortex XDR data. A Discovery BIOC rule can use various event types, such as file, injection, load image, network, process, registry, or user, to define the criteria for the rule. A Discovery BIOC rule can also use operators, functions, and variables to create complex logic and conditions for the rule. A Discovery BIOC rule can generate alerts when the rule is triggered, and these alerts can be grouped into incidents for further investigation and response12.

Let’s briefly discuss the other options to provide a comprehensive explanation:

A. Threat Actor: This is not the correct answer. Threat Actor is not a type of BIOC rule that is currently available in Cortex XDR. Threat Actor is a term that refers to an individual or a group that is responsible for a cyberattack or a threat campaign. Cortex XDR does not support creating BIOC rules based on threat actors, but it can provide threat intelligence and context from various sources, such as Unit 42, AutoFocus, or Cortex XSOAR3.

C. Network: This is not the correct answer. Network is not a type of BIOC rule that is currently available in Cortex XDR. Network is an event type that can be used in a Discovery BIOC rule to define the criteria based on network attributes, such as source IP, destination IP, source port, destination port, protocol, or domain. Network is not a standalone type of BIOC rule, but a part of the Discovery BIOC rule2.

D. Dropper: This is not the correct answer. Dropper is not a type of BIOC rule that is currently available in Cortex XDR. Dropper is a term that refers to a type of malware that is designed to download and install other malicious files or programs on a compromised system. Cortex XDR does not support creating BIOC rules based on droppers, but it can detect and prevent droppers using various methods, such as behavioral threat protection, exploit prevention, or WildFire analysis4.

In conclusion, the type of BIOC rule that is currently available in Cortex XDR is Discovery. By using Discovery BIOC rules, you can create custom detection rules that match your specific use cases and scenarios.

Ransomware is a type of malicious software, or malware, that encrypts user files and prevents them from accessing their data until they pay a ransom. Ransomware can affect individual users, businesses, and organizations of all kinds. Ransomware attacks can cause costly disruptions, data loss, and reputational damage. Ransomware can spread through various methods, such as phishing emails, malicious attachments, compromised websites, or network vulnerabilities. Some ransomware variants can also self-propagate and infect other devices or networks. Ransomware authors typically demand payment in cryptocurrency or other untraceable methods, and may threaten to delete or expose the encrypted data if the ransom is not paid within a certain time frame. However, paying the ransom does not guarantee that the files will be decrypted or that the attackers will not target the victim again. Therefore, the best way to protect against ransomware is to prevent infection in the first place, and to have a backup of the data in case of an attack123456

Ransomware is a type of malicious software, or malware, that encrypts certain files or data on the victim’s system or network and prevents them from accessing their data until they pay a ransom. This is by far the most common tactic used by ransomware to shut down a victim’s operation, as it can cause costly disruptions, data loss, and reputational damage. Ransomware can affect individual users, businesses, and organizations of all kinds. Ransomware can spread through various methods, such as phishing emails, malicious attachments, compromised websites, or network vulnerabilities. Some ransomware variants can also self-propagate and infect other devices or networks. Ransomware authors typically demand payment in cryptocurrency or other untraceable methods, and may threaten to delete or expose the encrypted data if the ransom is not paid within a certain time frame. However, paying the ransom does not guarantee that the files will be decrypted or that the attackers will not target the victim again. Therefore, the best way to protect against ransomware is to prevent infection in the first place, and to have a backup of the data in case of an attack1234

Phishing is a technique that belongs to two MITRE ATT&CK tactics: Reconnaissance and Initial Access. Reconnaissance is the process of gathering information about a target before launching an attack. Phishing for information is a sub-technique of Reconnaissance that involves sending phishing messages to elicit sensitive information that can be used during targeting. Initial Access is the process of gaining a foothold in a network or system. Phishing is a sub-technique of Initial Access that involves sending phishing messages to execute malicious code on victim systems. Phishing can be used for both Reconnaissance and Initial Access depending on the objective and content of the phishing message. References:

Phishing, Technique T1566 - Enterprise | MITRE ATT&CK® 1

Phishing for Information, Technique T1598 - Enterprise | MITRE ATT&CK® 2

Phishing for information, Part 2: Tactics and techniques 3

PHISHING AND THE MITREATT&CK FRAMEWORK - EnterpriseTalk 4

Initial Access, Tactic TA0001 - Enterprise | MITRE ATT&CK® 5

 The Live Terminal feature in Cortex XDR allows you to initiate a remote connection to an endpoint and perform various actions such as running commands, uploading and downloading files, and terminating processes. You can disable the ability to use the Live Terminal feature in Cortex XDR by configuring the Agent Settings Profile. The Agent Settings Profile defines the behavior and functionality of the Cortex XDR agent on the endpoint. You can create different profiles for different groups of endpoints and assign them accordingly. To disable the Live Terminal feature, you need to uncheck the Enable Live Terminal option in the Agent Settings Profile and save the changes. This will prevent the Cortex XDR agent from accepting any Live Terminal requests from the Cortex XDR management console. References:

Live Terminal: This document explains how to use the Live Terminal feature to investigate and respond to security events on Windows endpoints.

Agent Settings Profile: This document describes how to create and manage Agent Settings Profiles to define the behavior and functionality of the Cortex XDR agent on the endpoint.

 A successful exploit is a piece of software or code that takes advantage of a vulnerability and executes malicious actions on the target system. A vulnerability is a weakness or flaw in a software or hardware component that can be exploited by an attacker. A successful exploit is one that achieves its intended goal, such as gaining unauthorized access, executing arbitrary code, escalating privileges, or compromising data.

In the given options, only B is an example of a successful exploit, because it involves a user executing code that exploits a vulnerability on a local service, such as a web server, a database, or a network protocol. This could allow the attacker to gain control over the service, access sensitive information, or perform other malicious actions.

Option A is not a successful exploit, because it involves connecting unknown media to an endpoint that copied malware due to Autorun. Autorun is a feature that automatically runs a program or script when a removable media, such as a USB drive, is inserted into a computer. This feature can be abused by malware authors to spread their malicious code, but it is not an exploit in itself. The malware still needs to exploit a vulnerability on the endpoint to execute its payload and cause damage.

Option C is not a successful exploit, because it involves identifying vulnerable services on a server. This is a step in the reconnaissance phase of an attack, where the attacker scans the target system for potential vulnerabilities that can be exploited. However, this does not mean that the attacker has successfully exploited any of the vulnerabilities, or that the vulnerabilities are even exploitable.

Option D is not a successful exploit, because it involves executing a process executable for well-known and signed software. This is a legitimate action that does not exploit any vulnerability or cause any harm. Well-known and signed software are programs that are widely used and trusted, and have a digital signature that verifies their authenticity and integrity. Executing such software does not pose a security risk, unless the software itself is malicious or compromised.

 When investigating security events, the feature in Cortex XDR that is useful for reverting the changes on the endpoint is Remediation Suggestions. Remediation Suggestions are a feature of Cortex XDR that provide you with recommended actions to undo the effects of malicious activity on your endpoints. You can view the remediation suggestions for each alert or incident in the Cortex XDR console, and decide whether to apply them or not. Remediation Suggestions can help you restore the endpoint to its original state, remove malicious files or processes, or fix registry or system settings. Remediation Suggestions are based on the forensic data collected by the Cortex XDR agent and the analysis performed by Cortex XDR. References:

Remediation Suggestions

Apply Remediation Suggestions

The Managed Threat Hunting (MTH) team is a group of security experts who proactively hunt for threats in the Cortex XDR tenant and generate a report with the findings. The MTH team uses advanced queries and investigative actions to identify and analyze potential threats, such as zero-day exploits, that may have bypassed the prevention and detection capabilities of Cortex XDR. The MTH team also provides recommendations and best practices to help customers remediate the threats and improve their security posture. References:

Managed Threat Hunting Service

Managed Threat Hunting Report

 When selecting multiple incidents at a time, the options that are available from the menu when a user right-clicks the incidents are: Assign incidents to an analyst in bulk and Change the status of multiple incidents. These options allow the user to perform bulk actions on the selected incidents, such as assigning them to a specific analyst or changing their status to open, in progress, resolved, or closed. These options can help the user to manage and prioritize the incidents more efficiently and effectively. To use these options, the user needs to select the incidents from the incident table, right-click on them, and choose the desired option from the menu. The user can also use keyboard shortcuts to perform these actions, such as Ctrl+A to select all incidents, Ctrl+Shift+A to assign incidents to an analyst, and Ctrl+Shift+S to change the status of incidents12

 The first protection module that is checked in the Cortex XDR Windows agent malware protection flow is the Hash Verdict Determination. This module compares the hash of the executable file that is about to run on the endpoint with a list of known malicious hashes stored in the Cortex XDR cloud. If the hash matches a malicious hash, the agent blocks the execution and generates an alert. If the hash does not match a malicious hash, the agent proceeds to the next protection module, which is the Restriction Policy1.

The Hash Verdict Determination module is the first line of defense against malware, as it can quickly and efficiently prevent known threats from running on the endpoint. However, this module cannot protect against unknown or zero-day threats, which have no known hash signature. Therefore, the Cortex XDR agent relies on other protection modules, such as Behavioral Threat Protection, Child Process Protection, and Exploit Protection, to detect and block malicious behaviors and exploits that may occur during the execution of the file1.

 To add an exception to exclude a specific file hash from examination by the Malware profile for a Windows endpoint, you need to use the Action Center in Cortex XDR. The Action Center allows you to create and manage actions that apply to endpoints, such as adding files or processes to the allow list or block list, isolating or unisolating endpoints, or initiating live terminal sessions. To add a file hash to the allow list, you need to choose Allow list, select new action, select add to allow list, add your hash to the list, and apply it. This will prevent the Malware profile from scanning or blocking the file on the endpoints that match the scope of the action. References: Cortex XDR 3: Responding to Attacks1, Action Center2

 UASLR stands for User Address Space Layout Randomization, which is a feature of Exploit Prevention Module (EPM) that provides better entropy for randomization of memory locations. UASLR adds entropy to the base address of the executable image and the heap, making it harder for attackers to predict the memory layout of a process. UASLR is enabled by default for all processes, but can be disabled or customized for specific applications using the EPM policy settings. References:

Exploit Prevention Module (EPM) entropy randomization memory locations

Exploit protection reference

 If all alerts contained in a Cortex XDR incident have exclusions, the Cortex XDR console will automatically mark the incident as Resolved – False Positive. This means that the incident was not a real threat, but a benign or legitimate activity that triggered an alert. By marking the incident as Resolved – False Positive, the Cortex XDR console removes the incident from the list of unresolved incidents and does not count it towards the incident statistics. This helps the analyst to focus on the true positive incidents that require further investigation and response1.

An exclusion is a rule that hides an alert from the Cortex XDR console, based on certain criteria, such as the alert source, type, severity, or description. An exclusion does not change the security policy or prevent the alert from firing, it only suppresses the alert from the console. An exclusion is useful when the analyst wants to reduce the noise of false positive alerts that are not relevant or important2.

An exception, on the other hand, is a rule that overrides the security policy and allows or blocks a process or file from running on an endpoint, based on certain attributes, such as the file hash, path, name, or signer. An exception is useful when the analyst wants to prevent false negative alerts that are caused by malicious or unwanted files or processes that are not detected by the security policy3.

A BIOC rule is a rule that creates an alert based on a custom XQL query that defines a specific behavior of interest or concern. A BIOC rule is useful when the analyst wants to detect and alert on anomalous or suspicious activities that are not covered by the default Cortex XDR rules4.

The Broker VM for Cortex XDR is a virtual machine that serves as the central communication hub for all Cortex XDR agents deployed in your organization. It enables agents to communicate with the Cortex XDR cloud service and allows you to manage and monitor the agents’ activities from a centralized location. The system requirements for the Broker VM are as follows:

CPU: 4 cores

RAM: 8 GB

Disk space: 256 GB

Network: Internet access and connectivity to all Cortex XDR agents

The disk space requirement is based on the number of agents and the frequency of content updates. The Broker VM stores the content updates locally and distributes them to the agents. The disk space also depends on the retention period of the content updates, which can be configured in the Broker VM settings. The default retention period is 30 days.

If you have an isolated network that is prevented from connecting to the Cortex Data Lake, you can use the Local Agent Proxy setup to facilitate the communication. The Local Agent Proxy is a type of Broker VM that acts as a proxy server for the Cortex XDR agents that are deployed on the isolated network. The Local Agent Proxy enables the Cortex XDR agents to communicate securely with the Cortex Data Lake and the Cortex XDR management console over the internet, without requiring direct access to the internet from the isolated network. The Local Agent Proxy also allows the Cortex XDR agents to download installation packages and content updates from the Cortex XDR management console. To use the Local Agent Proxy setup, you need to deploy a Broker VM on the isolated network and configure it as a Local Agent Proxy. You also need to deploy another Broker VM on a network that has internet access and configure it as a Remote Agent Proxy. The Remote Agent Proxy acts as a relay between the Local Agent Proxy and the Cortex Data Lake. You also need to install a strong cipher SHA256-based SSL certificate on both the Local Agent Proxy and the Remote Agent Proxy to ensure secure communication. You can read more about the Local Agent Proxy setup and how to configure it here1 and here2. References:

Local Agent Proxy

Configure the Local Agent Proxy Setup

The Incident Management Dashboard provides a high-level overview of the incident response process, including the Mean Time to Resolution (MTTR) metric. This metric measures the average time it takes to resolve an incident from the moment it is created to the moment it is closed. The dashboard also shows the number of incidents by status, severity, and assigned analyst, as well as the top alerts by category, source, and destination. The Incident Management Dashboard is designed for executives and managers who want to monitor the performance and efficiency of their security teams. References: [PCDRA Study Guide], page 18.

 A global exception is a rule that allows you to exclude specific files, processes, or behaviors from being blocked or detected by Cortex XDR. A global exception applies to all endpoints in your organization that are protected by Cortex XDR. Creating a global exception for a vitally important piece of software that is known to be benign would prevent Cortex XDR from blocking this software in the future, for all endpoints in your organization.

To create a global exception, you need to follow these steps:

In the Cortex XDR management console, go to Policy Management > Exceptions and click Add Exception.

Select the Global Exception option and click Next.

Enter a name and description for the exception and click Next.

Select the type of exception you want to create, such as file, process, or behavior, and click Next.

Specify the criteria for the exception, such as file name, hash, path, process name, command line, or behavior name, and click Next.

Review the summary of the exception and click Finish.

 Live terminal uses Python 3 with standard Python libraries to run Python commands and scripts on the endpoint. Live terminal does not support Python 2 or any custom or external Python libraries. Live terminal uses the Python interpreter embedded in the Cortex XDR agent, which is based on Python 3.7.4. The standard Python libraries are the modules that are included with the Python installation and provide a wide range of functionalities, such as operating system interfaces, network programming, data processing, and more. You can use the Python commands and scripts to perform advanced tasks or automation on the endpoint, such as querying system information, modifying files or registry keys, or running other applications. References:

Run Python Commands and Scripts

Python Standard Library

To ensure that the same protection is extended to all your servers, you need to create Behavioral Threat Protection (BTP) rules to recognize and prevent the activity. BTP is a feature of Cortex XDR that allows you to create custom rules that detect and block malicious or suspicious behaviors on your endpoints, such as file execution, process injection, network connection, or registry modification. BTP rules can use various operators, functions, and variables to define the criteria and the actions for the rules. By creating BTP rules that match the behaviors of the supply chain attack, you can prevent the attack from compromising your servers12.

Let’s briefly discuss the other options to provide a comprehensive explanation:

B. Enable DLL Protection on all servers but there might be some false positives: This is not the correct answer. Enabling DLL Protection on all servers will not ensure that the same protection is extended to all your servers. DLL Protection is a feature of Cortex XDR that allows you to block the execution of unsigned or untrusted DLL files on your endpoints. DLL Protection can help to prevent some types of attacks that use malicious DLL files, but it may not be effective against the supply chain attack that used a Trojanized DLL file that was digitally signed by a trusted vendor. DLL Protection may also cause some false positives, as it may block some legitimate DLL files that are unsigned or untrusted3.

C. Create IOCs of the malicious files you have found to prevent their execution: This is not the correct answer. Creating IOCs of the malicious files you have found will not ensure that the same protection is extended to all your servers. IOCs are indicators of compromise that you can create to detect and respond to known threats on your endpoints, such as file hashes, registry keys, IP addresses, domain names, or full paths. IOCs can help to identify and block the malicious files that you have already discovered, but they may not be effective against the supply chain attack that used different variants of the malicious files with different hashes or names. IOCs may also become outdated, as the attackers may change or update their files to evade detection4.

D. Enable Behavioral Threat Protection (BTP) with cytool to prevent the attack from spreading: This is not the correct answer. Enabling BTP with cytool will not ensure that the same protection is extended to all your servers. BTP is a feature of Cortex XDR that allows you to create custom rules that detect and block malicious or suspicious behaviors on your endpoints, such as file execution, process injection, network connection, or registry modification. BTP rules can help to prevent the attack from spreading, but they need to be created and configured in the Cortex XDR app, not with cytool. Cytool is a command-line tool that allows you to perform various operations on the Cortex XDR agent, such as installing, uninstalling, upgrading, or troubleshooting. Cytool does not have an option to enable or configure BTP rules.

In conclusion, to ensure that the same protection is extended to all your servers, you need to create BTP rules to recognize and prevent the activity. By using BTP rules, you can create custom and flexible prevention rules that match the behaviors of the supply chain attack.

 A common sequence of cyber-attack tactics is based on the Cyber Kill Chain model, which describes the stages of a cyber intrusion from the perspective of the attacker. The Cyber Kill Chain model consists of seven phases: reconnaissance, weaponization, delivery, exploitation, installation, command and control, and actions on the objective. These phases are briefly explained below:

Reconnaissance: The attacker gathers information about the target, such as its network, systems, vulnerabilities, employees, and business operations. The attacker may use various methods, such as scanning, phishing, or searching open sources, to collect data that can help them plan the attack.

Weaponization: The attacker creates or obtains a malicious payload, such as malware, exploit, or script, that can be used to compromise the target. The attacker may also embed the payload into a delivery mechanism, such as an email attachment, a web link, or a removable media.

Delivery: The attacker sends or delivers the weaponized payload to the target, either directly or indirectly. The attacker may use various channels, such as email, web, or physical access, to reach the target’s network or system.

Exploitation: The attacker exploits a vulnerability or weakness in the target’s network or system to execute the payload. The vulnerability may be technical, such as a software flaw, or human, such as a social engineering trick.

Installation: The attacker installs or drops additional malware or tools on the target’s network or system to establish a foothold and maintain persistence. The attacker may use various techniques, such as registry modification, file manipulation, or process injection, to hide their presence and evade detection.

Command and Control: The attacker establishes a communication channel between the compromised target and a remote server or controller. The attacker may use various protocols, such as HTTP, DNS, or IRC, to send commands and receive data from the target.

Actions on the objective: The attacker performs the final actions that achieve their goal, such as stealing data, destroying files, encrypting systems, or disrupting services. The attacker may also try to move laterally within the target’s network or system to access more resources or data.

The Host Insights module provides the best visibility to view vulnerabilities on your endpoints. The Host Insights module is an add-on feature for Cortex XDR that combines vulnerability management, application and system visibility, and a Search and Destroy feature to help you identify and contain threats. The vulnerability management feature allows you to scan your Windows endpoints for known vulnerabilities and missing patches, and view the results in the Cortex XDR console. You can also filter and sort the vulnerabilities by severity, CVSS score, CVE ID, or patch availability. The Host Insights module helps you reduce your exposure to threats and improve your security posture. References:

Host Insights

Vulnerability Management

The Windows Registry is a hierarchical database that stores settings for the operating system and for applications that run on Windows. The registry contains information, settings, options, and other values for programs and hardware installed on all versions of Microsoft Windows operating systems. The registry is organized into five main sections, called hives, each of which contains keys, subkeys, and values. The Cortex XDR agent uses the registry to store its configuration, status, and logs, as well as to monitor and control the endpoint’s security features. The Cortex XDR agent also allows you to run scripts that can read, write, or delete registry keys and values on the endpoint. References:

Windows Registry - Wikipedia

Registry Operations

 The output shows the top 10 hosts with the most malware in the last 30 days, based on the Cortex XDR data. The output is sorted by the number of incidents, with the host with the most incidents at the top. The output also shows the number of alerts, the number of endpoints, and the percentage of endpoints for each host. The output is generated by using the ACC (Application Command Center) feature of Cortex XDR, which provides a graphical representation of the network activity and threat landscape. The ACC allows you to view and analyze various widgets, such as the Top 10 hosts with the most malware, the Top 10 applications by bandwidth, the Top 10 threats by count, and more .