You can access these events in Windows Event viewer: Type event viewer in the Start menu and open the Windows Event Viewer. See Example Base Policies. [!NOTE] Learn how to centrally discover and deploy Microsoft Sentinel out-of-the-box content and solutions. Microsoft has observed attackers using many of the same inventory techniques to locate targets. [!div class="mx-imgBorder"] [!div class="mx-imgBorder"] To access the Attack surface reduction rules report in the Microsoft 365 Security dashboard, the following permissions are required: For more information about user role management, see Create and manage roles for role-based access control. These new capabilities provide security teams with the following: To use this feature, open the Exposed devices tab in the dedicated CVE-2021-44228 dashboard and review the Mitigation status column. Below is a chart displaying each ASR rule in the respective categories. In January, we started seeing attackers taking advantage of the vulnerabilities in internet-facing systems, eventually deploying ransomware. The features won't block or prevent apps, scripts, or files from being modified. You can learn more on how to customize ASR rules byexcluding files and foldersoradding custom text to the notificationalert that appears on a user's computer. [12/22/2021] Added new protections across Microsoft 365 Defender, including Microsoft Defender for Office 365. In this case, it applied my new ASR rule policy to all devices I targeted successfully. Figure 20. Before you begin testing ASR rules, it is recommended that you first disable all rules that you have previously set to either audit or enable (if applicable). Threat and vulnerability management finds exposed devices based on vulnerable software and vulnerable files detected on disk. Attack surfaces are all the places where your organization is vulnerable to cyberthreats and attacks. In the Microsoft 365 Defender portal, go to Vulnerability management > Dashboard > Threat awareness, then click View vulnerability details to see the consolidated view of organizational exposure to the Log4j 2 vulnerability (for example, CVE-2021-44228 dashboard, as shown in the following screenshots) on the device, software, and vulnerable component level. ASR rules event viewer." When you select the policy name that you have created, you will be redirected to the overview page which will display more detailed information. It surfaces exploitation but may surface legitimate behavior in some environments. We have released two new threat and vulnerability management capabilities that can significantly simplify the process of turning off JNDI lookup, a workaround that can prevent the exploitation of the Log4j vulnerabilities on most devices, using an environment variable called LOG4J_FORMAT_MSG_NO_LOOKUPS. The attack surface reduction (ASR) rules report provides information about the attack surface reduction rules that are applied to devices in your organization. Protect and maintain the integrity of a system as it starts and while it's running. Suspected exploitation of Log4j vulnerability. :::image type="content" source="images/asrrecommendation.png" alt-text="The ASR recommendation" lightbox="images/asrrecommendation.png"::: In the recommendation details pane, check for user impact to determine what percentage of your devices can accept a new policy enabling the rule in blocking mode without adversely affecting productivity. We discovered that the vulnerability, now tracked as CVE-2021-35247, is an input validation vulnerability that could allow attackers to build a query given some input and send that query over the network without sanitation. . lightbox="images/attack-surface-reduction-rules-report-main-detections-configuration-card.png"::: Click View detections to open the Detections tab. Thanks for reading and have a great Cybersecurity day! Note: We recommend that you check the solution for updates periodically, as new collateral may be added to this solution given the rapidly evolving situation. As the filter currently functions in this release, every time you want to "group by", you must first scroll down to last detection in the list to load the complete data set. Applicability rules has more information. Clicking on the ASR rules configuration link at the top of the card also opens the main Attack surface reduction rules Configuration tab. ARG provides another way to query resource data for resources found to be affected by the Log4j vulnerability. Microsoft 365 Defender coordinates multiple security solutions that detect components of observed attacks taking advantage of this vulnerability, from exploitation attempts to remote code execution and post-exploitation activity. license, this link will open the Microsoft Defender 365 Reports > Attack surface reductions > Exclusions tab. Limited management options. The next tab, Configuration settings is where you will configure the ASR rules. Select Devices and then All devices to make sure the device you will be applying the new ASR rule Policy has been synced. To enable an attack surface reduction rule in audit mode, use the following PowerShell cmdlet: Where is a GUID value of the attack surface reduction rule. We are listing them here, as it is highly recommended that they are triaged and remediated immediately given their severity and the potential that they could be related to Log4j exploitation: Some of the alerts mentioned above utilize the enhanced network inspection capabilities in Microsoft Defender for Endpoint. Under List of additional folders that need to be protected, List of apps that have access to protected folders, and Exclude files and paths from attack surface reduction rules, enter individual Attack surface reduction rules can constrain software-based risky behaviors and help keep your organization safe. Enter the words, Event Viewer, into the Start menu to open the Windows Event Viewer. The updates include the following: To complement this new table, the existing DeviceTvmSoftwareVulnerabilities table in advanced hunting can be used to identify vulnerabilities in installed software on devices: These capabilities integrate with the existing threat and vulnerability management experience and are gradually rolling out. This hunting query looks in Azure Web Application Firewall data to find possible exploitation attempts for CVE-2021-44228 involving Log4j vulnerability. If ASR rules are detecting files that you believe shouldn't be detected, you should use audit mode first to test the rule. Some would include scope tags such as The_Citadel IT Team, Mr_Robot_ITDepartment, or Test-OU. Sample email with malicious sender display name. Selecting the groups to include and IT Group will target the devices inside the group and then click select and then click next. Select the Log4j vulnerability detection solution, and click Install. If you have a Microsoft Defender 365 E5 (or Windows E5?) Use the checkboxes next to your list of exclusion entries to select items to Delete, Sort, Import, or Export. Sharing best practices for building any app with .NET. After you have loaded the complete data set, you can then launch the "sort by" filtering. Click on the view detections tab to see a more fine-grained ASR rule detection graph in Audit and Block mode over a period time and what has been detected. If you've already registered, sign in. The bottom section of the report lists detected threats - on a per-device basis - with the following fields: For more information about ASR rule audit and block modes, see Attack surface reduction rule modes. [!NOTE] When filtering by rule, the number of individual detected items listed in the lower half of the report is currently limited to 200 rules. This query looks for alert activity pertaining to the Log4j vulnerability. An attack surface is defined as the entire network landscape of an organization that is susceptible to hacking. November 4, 2022 by Jitesh Kumar Learn how to configure Attack Surface Reduction ASR Rules in Intune. Review base policies in Windows. Microsoft Defender for IoT alert. Use attack surface reduction rules to prevent malware infection. Device groupsIf you want to apply settings on a device, regardless of who's signed in, then assign your profiles to a devices group. The Possible exclusion and impact section provides impact of the selected file or process. Suspicious process event creation from VMWare Horizon TomcatService. Creating mitigation actions for exposed devices. Viewing each devices mitigation status. Microsoft has observed activities including installing coin miners, using Cobalt Strike to enable credential theft and lateral movement, and exfiltrating data from compromised systems. Every customer environment is different both in the architectural design and what is allowed or not allowed in the environment which might cause a line of business application to not work. This report also provides information about: detected threats blocked threats devices that aren't configured to use the standard protection rules to block threats Defender for Endpoint includes several capabilities to help reduce your attack surfaces. Organizations may not realize their environments may already be compromised. Use application control so that your applications must earn trust in order to run. The Add exclusions tab presents a ranked list of detections by file name and provides a method to configure exclusions. List of attack surface reduction events. You can also use role-based access control and scope tags to make sure that the right admins have the right access and visibility to the right Intune objects. For more information about threat intelligence packages in Defender for IoT, please refer to the documentation. On the far right, you can change the time from last 24 hours, last 7 days, last 30 days, or a custom time range of your choosing. Warn mode isn't supported for three attack surface reduction rules when you configure them in Microsoft Intune. [!NOTE] The summary report cards for ASR rules are shown in the following figure. Attack Surface Reduction (ASR) are rules that are part of Windows Defender Exploit Guard that block certain processes and activities, with the aim of limiting risks and helping to protect your organization. You can also manually navigate to the event area that corresponds to the feature. In the HabitsRAT case, the campaign was seen overlapping with infrastructure used in prior campaigns. Threat and vulnerability management dedicated CVE-2021-44228 dashboard, Figure 3. ASR rules fall into specific categories which are Microsoft Office, email based, Windows Management Interface (WMI) based, executable and script based, 3rd party application based, Windows credentials based, and device control based. This query identifies anomalous child processes from the ws_TomcatService.exe process associated with the exploitation of the Log4j vulnerability in VMWare Horizon installations. Threat and vulnerability management automatically and seamlessly identifies devices affected by the Log4j vulnerabilities and the associated risk in the environment and significantly reduces time-to-mitigate. For example, you have devices that print tickets, scan inventory, are shared by shift workers, are assigned to a specific warehouse, and so on. Finding vulnerable software via advanced hunting. See Requirements in the "Enable attack surface reduction rules" article for information about supported operating systems and additional requirement information. Now lets head over to finalizing up the newly created profile on the review and create profile page. Typically, the recommendation is that you enable all the rules (in Audit) so that you can determine which rules are triggered during the testing phase. An example pattern of attack would appear in a web request log with strings like the following: An attacker performs an HTTP request against a target system, which generates a log using Log4j 2 that leverages JNDI to perform a request to the attacker-controlled site. When you create or update a profile, you can add scope tags and applicability rules to the profile. In many observed attacks, the attacker-owned parameter is a DNS logging system, intended to log a request to the site to fingerprint the vulnerable systems. It returns a table of suspicious command lines. Microsofts unified threat intelligence team, comprising the Microsoft Threat Intelligence Center (MSTIC), Microsoft 365 Defender Threat Intelligence Team, RiskIQ, and the Microsoft Detection and Response Team (DART), among others, have been tracking threats taking advantage of the remote code execution (RCE) vulnerabilities in Apache Log4j 2 referred to as Log4Shell. In these attacks, HAFNIUM-associated systems were observed using a DNS service typically associated with testing activity to fingerprint systems. Sign up for a free trial. (If you use Group Policy to configure your attack surface reduction rules, warn mode is supported.) Log4j binaries are discovered whether they are deployed via a package manager, copied to the image as stand-alone binaries, or included within a JAR Archive (up to one level of nesting). Here we are targeting just a select group and will pick the IT Group for this new policy. For customers who have already enabled DRS 1.0/1.1 or CRS 3.0/3.1, no action is needed. You can customize the notification with your company details and contact information. For a sequential, end-to-end process of how to manage ASR rules, see: You can assess how an attack surface reduction rule might affect your network by opening the security recommendation for that rule in Microsoft Defender Vulnerability Management. :::image type="content" source="images/asr-defender365-05b-mem3.png" alt-text="The Endpoint security Attack surface reduction pane" lightbox="images/asr-defender365-05b-mem3.png"::: [!NOTE] Microsoft has observed rapid uptake of the vulnerability into existing botnets like Mirai, existing campaigns previously targeting vulnerable Elasticsearch systems to deploy cryptocurrency miners, and activity deploying the Tsunami backdoor to Linux systems. Provides steps to use audit mode to test attack surface reduction rules. Begin your attack surface reduction (ASR) rules deployment with ring 1. :::image type="content" source="images/asr-rules-testing-steps.png" alt-text="The Microsoft Defender for Endpoint (MDE) attack surface reduction (ASR rules) test steps. Microsoft Sentinel also provides a CVE-2021-44228 Log4Shell Research Lab Environment for testing the vulnerability: https://github.com/OTRF/Microsoft-Sentinel2Go/tree/master/grocery-list/Linux/demos/CVE-2021-44228-Log4Shell. Although attack surface reduction rules don't require a Windows E5 license, if you have Windows E5, you get advanced management capabilities. Want to experience Microsoft Defender for Endpoint? Microsoft is a leader in cybersecurity, and we embrace our responsibility to make the world a safer place. [12/27/2021] New capabilities in threat and vulnerability management including a new advanced hunting schema and support for Linux, which requires updating the Microsoft Defender for Linux client; new Microsoft Defender for Containers solution. Double-click on the sub item to see events. If possible, it then decodes the malicious command for further analysis. Clicking on the Chart type, you can view all the data in a table, column chart, stacked column chart, pie chart, donut chart, line chart, scatter chart, and area chart. 5007 -> Event when settings are changed. You can also determine if any settings are too "noisy" or impacting your day to day workflow. When you select a tile from this view, MEM displays additional details for that profile if they are available. Creating a new ASR Rule PolicyThe first item we want to do is make sure that all the devices we want to push the new ASR rule policy are showing up inside MEM admin center. To review apps that would have been blocked, open Event Viewer and filter for Event ID 1121 in the Microsoft-Windows-Windows Defender/Operational log. button in the Microsoft 365 Defender portal. You can use Export to save the full list of detections to Excel. Microsoft Defender ATP provides detailed reporting for events and blocks, as part of its alert investigation scenarios. Attack Surface Reduction Hi, I need to get a list of device which have the Asr rules applied to them in Audit mode I can see the list of these devices in the Reports > Attack Surface Reduction rules, however no way to export these into a spreadsheet. Get detailed reporting into events, blocks, and warnings as part of Windows Security if you have an E5 subscription and use Microsoft Defender for Endpoint. You plan to attack surface reduction (ASR) rules for the Windows 10 devices. Always place each rule in Audit first to monitor for testing of the policy before moving any of the rules into Enable (Block) mode. If the event is a true positive, the contents of the Body argument are Base64-encoded results from an attacker-issued comment. Microsoft has also continued to observe malicious activity performing data leakage via the vulnerability without dropping a payload. Log4j Vulnerability Detection solution in Microsoft Sentinel. Hope to see you inmynextblogand always protect your endpoints! Provide a policy name, e.g., ASR rules. Recommendation: Customers are recommended to enable WAF policy with Default Rule Set 1.0/1.1 on their Front Door deployments, or with OWASP ModSecurity Core Rule Set (CRS) versions 3.0/3.1 on Application Gateway V2 to immediately enable protection from this threat, if not already enabled. Our investigation shows that successful intrusions in these campaigns led to the deployment of the NightSky ransomware. Searching vulnerability assessment findings by CVE identifier, Figure 10. There are three main aspects to the Configuration tab: Basic rules Provides a method to toggle results between Basic rules and All Rules. You can query Defender for Endpoint data in Microsoft 365 Defender by using advanced hunting. To add a layer of protection against exploits that may be delivered via email, Microsoft Defender for Office 365 flags suspicious emails (e.g., emails with the jndi string in email headers or the sender email address field), which are moved to the Junk folder. For example, its possible to surface all observed instances of Apache or Java, including specific versions. By nature of Log4j being a component, the vulnerabilities affect not only applications that use vulnerable libraries, but also any services that use these applications, so customers may not readily know how widespread the issue is in their environment. There is high potential for the expanded use of the vulnerabilities. By monitoring audit data and adding exclusions for necessary applications, you can deploy attack surface reduction rules without reducing productivity. [!div class="mx-imgBorder"] Specifically, this is done by using cyber security tools to minimize the places where your organization is vulnerable to cyber attacks. For more information about interpreting log events, . Microsoft advises customers to investigate with caution, as these alerts dont necessarily indicate successful exploitation: The following alerts detect activities that have been observed in attacks that utilize at least one of the Log4j vulnerabilities. This technique is often used by attackers and was recently used to exploit the vulnerability in Log4j component of Apache to evade detection and stay persistent or for more exploitation in the network. What are Attack Surface Reduction rules? Enabling audit mode only for testing helps to prevent audit mode from affecting your line-of-business apps. This can be verified on the main Content hub page. What are Attack Surface Reduction Rules?Attack surface reduction ruleshelp prevent software behaviors that are often abused to compromise your device or network. These access brokers then sell access to these networks to ransomware-as-a-service affiliates. Defender for Endpoint includes several capabilities to help reduce your attack surfaces. Remote Code Execution rule for OWASP ModSecurity Core Rule Set (CRS) version 3.1. Filtering provides a way for you to specify what results are returned: When filtering by rule, the number of individual detected items listed in the lower half of the report is currently limited to 200 rules. Defender for Endpoint provides detailed reporting for events and blocks as part of alert investigation scenarios. The answer depends on your goal. In these cases, an adversary sends a malicious in-game message to a vulnerable Minecraft server, which exploits CVE-2021-44228 to retrieve and execute an attacker-hosted payload on both the server and on connected vulnerable clients. However, these behaviors are often considered risky because they're commonly abused by attackers through malware. Put these devices in a devices group, and assign your profiles to this devices group. In the Configuration settings tab, under Attack Surface Reduction Rules, set all rules to Audit mode. There are some variations in ASR rules reports. You can query Microsoft Defender ATP data by using advanced hunting. As we take a look at the ASR rule Audit report, we can see the Action Type is the ASR rule that was audited and then the file name, folder path, and other columns in the report. Specify a name for your filter. It is advisable to enable the ASR rules in the audit mode first so you will not run in to issues. The wide use of Log4j across many suppliers products challenge defender teams to mitigate and address the risks posed by the vulnerabilities (CVE-2021-44228 or CVE-2021-45046). It is also supported on Windows Server 2012 R2 and Windows Server 2016 using the Microsoft Defender for Endpoint solution for earlier Windows server versions. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Use the additional data field across all returned results to obtain details on vulnerable resources: Microsoft Sentinel customers can use the following detection query to look for devices that have applications with the vulnerability: This query uses the Microsoft Defender for Cloud nested recommendations data to find machines vulnerable to Log4j CVE-2021-44228. This hunting query identifies a match across various data feeds for IP IOCs related to the Log4j exploit described in CVE-2021-44228. Testing Microsoft Defender for Endpoint (MDE) attack surface reduction (ASR) rules helps you determine if rules will impede line-of-business operations prior to enabling any rule. [!NOTE] Attackers use of this malware or intent is not known at this time, but the campaign and infrastructure have been in use and have been targeting both Linux and Windows systems prior to this vulnerability. Block: Enable the ASR rule3. Weve seen things like running a lower or upper command within the exploitation string and even more complicated obfuscation attempts, such as the following, that are all trying to bypass string-matching detections: The vast majority of observed activity has been scanning, but exploitation and post-exploitation activities have also been observed. Finding vulnerable applications and devices via software inventory. Use Defender for Endpoint to get greater details for each event. Microsoft recommends customers to do additional review of devices where vulnerable installations are discovered. Microsoft Defender for Clouds threat detection capabilities have been expanded to surface exploitation of CVE-2021-44228 in several relevant security alerts: Microsoft Defender for IoT has released a dedicated threat Intelligence update package for detecting Log4j 2 exploit attempts on the network (example below). As an example, a path might be defined as: "c:\Windows" or C:\Users\jobarbar\Documents\Pen_Testing\Red_Team_Attack_Tools to exclude all files in this directory. Also, when certain attack surface reduction rules are triggered, alerts are generated. For more information about using the ASR rules report to manage ASR rules, see Attack surface reduction rules reports. ]net, and 139[.]180[.]217[.]203. In addition, this email event as can be surfaced via advanced hunting: Figure 18. In the Configuration settings pane, select Attack Surface Reduction and then select the desired setting for each ASR rule. We have deployed ASR rules using Microsoft System Center Configuration Manager in audit mode. Audit ASR rules, configure ASR rules exclusions. Excluded files are allowed to run, and no report or event will be recorded. To access the Attack surface reduction rules report, read permissions are required for the Microsoft 365 Defender portal. This query identifies a unique string present in malicious PowerShell commands attributed to threat actors exploiting vulnerable Log4j applications. Scroll through the events to find the one you are looking. You can enable audit mode for features or settings, and then review what would have happened if they were fully enabled. This query uses syslog data to alert on any attack toolkits associated with massive scanning or exploitation attempts against a known vulnerability. Enable automatic updating on theDefender for IoT portalby onboarding your cloud-connected sensor with the toggle for Automatic Threat Intelligence Updates turned on. The attack surface reduction (ASR) rules report provides information about the attack surface reduction rules that are applied to devices in your organization. This query looks for possibly vulnerable applications using the affected Log4j component. To configure attack surface reduction in your environment, follow these steps: Enable hardware-based isolation for Microsoft Edge. Learn more in the main Attack surface reduction rules article. You can enable audit mode using Group Policy, PowerShell, and configuration service providers (CSPs). If you have a Microsoft Defender 365 E5 (or Windows E5?) Weve observed the dropping of additional remote access toolkits and reverse shells via exploitation of CVE-2021-44228, which actors then use for hands-on-keyboard attacks. Enable attack surface reduction rules Enable application control. An example pattern of attack would appear in a web request log with strings like the following: . :::image type="content" source="images/attack-surface-reduction-rules-report-configuration-add-to-policy.png" alt-text="Screenshot that shows the ASR rules fly-out to add ASR rules to devices." Introduction of a new schema in advanced hunting. Attackers may attempt to launch arbitrary code by passing specific commands to a server, which are then logged and executed by the Log4j component.