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[Vulnerabilities](https://unit42.paloaltonetworks.com/category/vulnerabilities/ "Vulnerabilities") [Vulnerabilities](https://unit42.paloaltonetworks.com/category/vulnerabilities/) # Palo Alto Networks Discloses New Attack Surface Targeting Microsoft IIS and SQL Server at Black Hat Asia 2021 ![Clock Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-clock.svg) 7 min read Related Products [![Advanced Threat Prevention icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/strata_RGB_logo_Icon_Color.png)Advanced Threat Prevention](https://unit42.paloaltonetworks.com/product-category/advanced-threat-prevention/ "Advanced Threat Prevention")[![Next-Generation Firewall icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/strata_RGB_logo_Icon_Color.png)Next-Generation Firewall](https://unit42.paloaltonetworks.com/product-category/next-generation-firewall/ "Next-Generation Firewall") * ![Profile Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-profile-grey.svg) By: * [Tao Yan](https://unit42.paloaltonetworks.com/author/tao-yan/) * [Qi Deng](https://unit42.paloaltonetworks.com/author/qi-deng/) * [Bo Qu](https://unit42.paloaltonetworks.com/author/bo-qu/) * [Zhibin Zhang](https://unit42.paloaltonetworks.com/author/zhibin-zhang/) * ![Published Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-calendar-grey.svg) Published:July 30, 2021 * ![Tags Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-category.svg) Categories: * [Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) * [Vulnerabilities](https://unit42.paloaltonetworks.com/category/vulnerabilities/) * ![Tags Icon](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-tags-grey.svg) Tags: * [Attack 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[In our presentation](https://i.blackhat.com/asia-21/Thursday-Handouts/as-21-Yan-Give-Me-a-Sql-Injection-I-Shall-Pwn-IIS-and-Sql-Server.pdf), we introduced a previously undisclosed technique to execute SQL queries on the remote database in IIS and SQL Server under SQL injection or ad hoc scenarios. We also discussed three typical cases picked from around 100 Jet vulnerabilities that we discovered in a three-month period. Here, we cover the details of the technique, which allows threat actors to remotely attack IIS and SQL Server to gain SYSTEM privilege by using Microsoft Jet Database Engine vulnerabilities. In response to this research, Microsoft released a complex patch to mitigate this attack surface. However, the patch is turned off by default and most Jet vulnerabilities are still not patched. We highly recommend that our customers proactively turn on mitigation to disable remote tables access in the registry and stay cautious of these kinds of attacks. Besides that, the mitigation for the attack surface in Access Connectivity Engine (ACE) still remains imperfect, and we are working with Microsoft to release a complete patch for both MS Jet and ACE. Palo Alto Networks [Next-Generation Firewall](https://www.paloaltonetworks.com/network-security/next-generation-firewall) customers can help mitigate such attacks by using App-ID and the [Threat Prevention](https://www.paloaltonetworks.com/products/secure-the-network/subscriptions/threat-prevention) security subscription. ## Attack Surface The new attack surface is caused by the remote database access supported in Microsoft Jet Database Engine, including MS Jet Red (Jet Red Database Engine) and ACE (Access Connectivity Engine). It is a practical feature, but can also bring potential security issues. When misused, the feature allows attackers to execute SQL queries on the fully controlled database file on the remote attacker's controlled server. Once the remote legitimate database file is replaced with a malformed database file, executing SQL queries on it could break the code precondition and assumptions in Microsoft Jet/ACE, leading to vulnerabilities in many Jet components. The overall impact and break in security boundaries from these Jet vulnerabilities depend on where the SQL query is executed. The typical attack scenarios are SQL injection and ad hoc. In these two scenarios, attackers can execute any SQL queries on the malformed databases in the IIS and SQL Server. The resulting Jet vulnerabilities will impact the IIS and SQL Server. In detail, users can assign a remote database when executing SQL queries on tables by adding a database path ahead of the table in MS Jet and using [OPENDATASOURCE](https://docs.microsoft.com/en-us/sql/t-sql/functions/opendatasource-transact-sql?view=sql-server-ver15), [OPENROWSET](https://docs.microsoft.com/en-us/sql/t-sql/functions/openrowset-transact-sql?view=sql-server-ver15) or [addlinkedserver](https://docs.microsoft.com/en-us/sql/relational-databases/system-stored-procedures/sp-addlinkedserver-transact-sql?view=sql-server-ver15) in ACE, as shown in Figure 1. ![Users can assign a remote database when executing SQL queries on tables by adding a database path ahead of the table in MS Jet and using OPENDATASOURCEopendatasource, OPENROWSET or addlinkedserver in ACE, as shown here.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-49.png) Figure 1. Remote database access SQL in Access and SQL Server. Inside MS Jet and ACE, CreateFile is called to open the remote database file in IIS and SQL Server. Given that the input path of the remote database is a UNC path, both Server Message Block (SMB) and Web-based Distributed Authoring and Versioning (WebDAV) will be used to open the remote database, as shown in Figure 2. ![Screenshot of the hidden feature for CreateFile(UNC) in IIS and SQL Server using SMB and WEBDAV.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-50.png) Figure 2. The hidden feature for CreateFile(UNC) in IIS and SQL Server. SQL injection and ad hoc are just two of the possible attack scenarios. Similarly, IIS and SQL Server are only two of the potential victims. Any components supporting MS Jet and ACE on Windows could be vulnerable, as long as the component allows users to execute any query on the controllable database with MS Jet and ACE. ## Vulnerabilities in IIS and SQL Server The remote database access gives attackers the capability of replacing a legitimate database with a malformed database. According to our research, replacing the database is one of the keys to finding vulnerabilities in MS Jet and ACE. Assuming that code development and testing in MS Jet and ACE might not consider the situation of the database being malformed, we had the idea of mutating both SQL queries and database files. With that fuzzing strategy, we have discovered around 100 vulnerabilities in MS Jet and ACE, as shown in Figure 3. Most of them can be used to attack IIS and SQL Server under SQL injection and ad hoc scenarios. ![List of vulnerabilities in MS Jet and ACE found through the fuzzing strategy used in our research.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/Screen-Shot-2021-07-29-at-2.36.52-PM.png) Figure 3. ~100 MS Jet vulnerabilities. In our presentation, we proved that just one byte change in the database file can lead to an MS Jet vulnerability, as shown in Figure 4. ![The screenshot shows how changing just one byte in the database file can lead to an MS Jet vulnerability.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-53.png) Figure 4. The power of one byte mutation of the database. ## Microsoft Patch With the Patch Tuesday update for Windows released in May 2021, Microsoft assigned [CVE-2021-28455](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-28455) to our discovery and patched the new attack surface we reported. The patch introduces an option for users to disable remote database access in the MS Jet component and ACE component. Instead of patching every single JET vulnerability, it mitigated the whole attack surface disclosed in our presentation in multiple applications that use MS Jet, such as IIS and Access. As we can see in Figure 5, there is a new field at offset 904h in the rgtib structure (represented by ebx register) for remote database access. It is set to 1 by default in the \_ltibAllocate function, which means it is enabled by default. ![There is a new field at offset 904h in the rgtib structure (represented by ebx register) for remote database access, as shown here. It is set to 1 by default in the \_ltibAllocate function, which means it is enabled by default.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-54.png) Figure 5. Default value set for new field AllowQueryRemoteTables in the rgtib structure. Then the UtilRegQueryValue2 function is called in the ErrReadRegistry function to get the value of the registry key -- AllowQueryRemoteTables -- under the HKEY\_LOCAL\_MACHINE\\SOFTWARE\\Microsoft\\Jet\\4.0\\engines registry entry. After that, it stores the value to the AllowQueryRemoteTables field of the rgtib structure shown in Figure 6. ![The value of the registry key is stored to the AllowQueryRemoteTables field on the rgtib structure shown here.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-28.jpeg) Figure 6. Get AllowQueryRemoteTables field from the registry in the UtilRegQueryValue2 function. After that, two functions ( \_ErrGetOutputDatabaseId and \_ErrQEMCompileQuery) check the AllowQueryRemoteTables field in the rgtib structure (represented by ecx register), as figure 7 depicts. ![Two functions check the AllowQueryRemoteTables field in the rgtib structure, as shown here.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-55.png) Figure 7. Check the AllowQueryRemoteTables field in the rgtib structure. As we can see in figure 8, if the AllowQueryRemoteTables field is set to 0, then the \_ErrGetOutputDatabaseId function will return an error and the ErrTryOpenDatabase function will not be invoked to open the database file, regardless of whether the database file is remote or local. This effectively mitigates the remote database access attack surface. ![As shown here, if the AllowQueryRemoteTables field is set to 0, then the \_ErrGetOutputDatabaseId function returns an error and the ErrTryOpenDatabase function will not be invoked to open the database file, which effectively mitigates the remote database access attack surface.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-56.png) Figure 8. AllowQueryRemoteTables field check in the \_ErrGetOutputDatabaseId function. However, this feature is not turned on by default. To disable remote database access, users need to add a registry, named AllowQueryRemoteTables, in corresponding registries as described in this [Microsoft document](https://support.microsoft.com/zh-cn/topic/kb5002984-configuring-jet-red-database-engine-and-access-connectivity-engine-to-block-access-to-remote-databases-56406821-30f3-475c-a492-208b9bd30544) and set the dword value to 0. ## Next-Generation Firewall Mitigations for CVE-2021-28455 Palo Alto Networks Next-Generation Firewall customers can configure their Security Policy Rule settings to protect themselves from attacks related to CVE-2021-28455 by blocking WebDAV traffic from traversing from the trusted to untrusted zones. #### How to configure App-ID to drop WebDAV packets: **Step 1**: Create a Security Policy Rule. 1. Select **Policies** \> **Security** and **Add**a new rule. 2. Enter a **Name** for the rule and add an optional **Description**. ![Example of filling out a Security Policy Rule in App-ID for the Next-Generation Firewall.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-57.png) Figure 9. Configuring Security Policy Rule. 3. On the **Source** tab, add "trust" to the **Source Zone.** ![Adding "trust" to the Source Zone under Security Policy Rule settings.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-58.png) Figure 10. Configuring Source Zone. 4. On the **Destination** tab, add "untrust" to the **Destination Zone.** ![Adding "untrust" to the Destination Zone under the Security Policy Rule.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-59.png) Figure 11. Configuring Destination Zone. 5. On the **Application** tab, add **WebDAV** to the **Applications.** ![Adding WebDAV to the Applications tab under the Security Policy Rule.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-60.png) Figure 12. Configuring applications. 6. On the **Actions** tab, use **Drop** action in **Action Setting.** ![Selecting actions under Security Policy Rule.](https://unit42.paloaltonetworks.com/wp-content/uploads/2021/07/word-image-61.png) Figure 13. Configuring actions. 7. Click **OK**. **Step 2** : **Commit** your changes. ## Conclusion IIS and SQL Server are examples of fundamental components in the Microsoft ecosystem that have been widely deployed in many production systems and services. Microsoft Jet Database Engine, including MS Jet and ACE, are over 20 years old, and a vast majority of the Jet modules have been found to be easily exploitable due to limited exploit mitigations. The remote database access feature connects the Jet vulnerabilities with IIS and SQL Server components, thereby downgrading their security to the same level as the Jet Database Engine. Attackers could potentially leverage this feature to attack IIS and SQL Server and get SYSTEM privilege remotely from a single SQL injection. Palo Alto Networks recommends all of our customers follow the Microsoft guidance and disable remote database access to mitigate this severe attack surface. This can help prevent attackers from using Jet vulnerabilities to compromise IIS and SQL Server. Palo Alto Networks Next-Generation Firewalls can help mitigate such attacks by using App-ID and the Threat Prevention security subscription. Back to top ### Tags * [Attack surface](https://unit42.paloaltonetworks.com/tag/attack-surface/ "attack surface") * [Black Hat](https://unit42.paloaltonetworks.com/tag/black-hat/ "Black Hat") * [Exploit](https://unit42.paloaltonetworks.com/tag/exploit/ "exploit") * [IIS](https://unit42.paloaltonetworks.com/tag/iis/ "IIS") * [JET](https://unit42.paloaltonetworks.com/tag/jet/ "JET") * [SQL](https://unit42.paloaltonetworks.com/tag/sql/ "SQL") [Threat Research Center](https://unit42.paloaltonetworks.com "Threat Research") [Next: Ransomware Families: 2021 Data to Supplement the Unit 42 Ransomware Threat Report](https://unit42.paloaltonetworks.com/ransomware-families/ "Ransomware Families: 2021 Data to Supplement the Unit 42 Ransomware Threat Report") ### Table of Contents * ### Related Articles * [Unit 42 Attack Surface Threat Research: Over 23% of Internet-Connected Exposures Involve Critical IT and Security Infrastructure](https://unit42.paloaltonetworks.com/2024-unit-42-attack-surface-threat-research-internet-connected-exposures/ "article - table of contents") * [In-Depth Analysis of July 2023 Exploit Chain Featuring CVE-2023-36884 and CVE-2023-36584](https://unit42.paloaltonetworks.com/new-cve-2023-36584-discovered-in-attack-chain-used-by-russian-apt/ "article - table of contents") * [When a Zero Day and Access Keys Collide in the Cloud: Responding to the SugarCRM Zero-Day Vulnerability](https://unit42.paloaltonetworks.com/sugarcrm-cloud-incident-black-hat/ "article - table of contents") ## Related Vulnerabilities Resources ![Pictorial representation of a group of people interacting with a dynamic 3D holographic display of colorful, undulating data waves on a table.](https://unit42.paloaltonetworks.com/wp-content/uploads/2025/09/11_Myth-Busting_Overview_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2025/08/Insights-icon-white.svg)Insights](https://unit42.paloaltonetworks.com/category/insights/) August 4, 2026 [#### The Frontier AI Vulnerability Burst: Industrializing Autonomous Zero-Day Discovery in Open-Source Software](https://unit42.paloaltonetworks.com/frontier-ai-vulnerability-burst/) * [AI](https://unit42.paloaltonetworks.com/tag/ai/ "AI") * [Frontier AI](https://unit42.paloaltonetworks.com/tag/frontier-ai/ "Frontier AI") * [Vulnerability Exploitation](https://unit42.paloaltonetworks.com/tag/vulnerability-exploitation/ "Vulnerability Exploitation") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/frontier-ai-vulnerability-burst/ "The Frontier AI Vulnerability Burst: Industrializing Autonomous Zero-Day Discovery in Open-Source Software") ![Pictorial representation of AI-enabled autonomous cyberattacks. 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Digital illustration of a map of North America with interconnected glowing lines and dots symbolizing network connections across the continent.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/05/06_Vulnerabilities_1920x900-3-1-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) May 6, 2026 [#### Threat Brief: Exploitation of PAN-OS Captive Portal Zero-Day for Unauthenticated Remote Code Execution](https://unit42.paloaltonetworks.com/captive-portal-zero-day/) * [CVE-2026-0300](https://unit42.paloaltonetworks.com/tag/cve-2026-0300/ "CVE-2026-0300") * [EarthWorm](https://unit42.paloaltonetworks.com/tag/earthworm/ "EarthWorm") * [PAN-OS](https://unit42.paloaltonetworks.com/tag/pan-os/ "PAN-OS") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/captive-portal-zero-day/ "Threat Brief: Exploitation of PAN-OS Captive Portal Zero-Day for Unauthenticated Remote Code Execution") ![Pictorial representation of a severe Linux vulnerability. Close-up of a woman wearing glasses and focusing intently on a computer screen.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/05/05_Vulnerabilities_1920x900-2-1-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) May 5, 2026 [#### Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years](https://unit42.paloaltonetworks.com/cve-2026-31431-copy-fail/) * [Containers](https://unit42.paloaltonetworks.com/tag/containers/ "Containers") * [CVE-2026-31431](https://unit42.paloaltonetworks.com/tag/cve-2026-31431/ "CVE-2026-31431") * [Kubernetes](https://unit42.paloaltonetworks.com/tag/kubernetes/ "Kubernetes") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/cve-2026-31431-copy-fail/ "Copy Fail: What You Need to Know About the Most Severe Linux Threat in Years") ![Pictorial representation of CVE-2023-33538. Abstract image of a glowing red Wi-Fi symbol on a circuit board, with intricate patterns and a futuristic appearance.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/04/04_Vulnerabilities_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) April 16, 2026 [#### A Deep Dive Into Attempted Exploitation of CVE-2023-33538](https://unit42.paloaltonetworks.com/exploitation-of-cve-2023-33538/) * [Botnet](https://unit42.paloaltonetworks.com/tag/botnet/ "botnet") * [Command injection](https://unit42.paloaltonetworks.com/tag/command-injection/ "Command injection") * [CVE-2023-33538](https://unit42.paloaltonetworks.com/tag/cve-2023-33538/ "CVE-2023-33538") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/exploitation-of-cve-2023-33538/ "A Deep Dive Into Attempted Exploitation of CVE-2023-33538") ![Pictorial representation of BeyondTrust vulnerability CVE-2026-1731. Digital art depicting a stylized mountain range with vibrant blue and red hues. The peaks are accentuated by glowing particles and an abstract, starry backdrop, creating a futuristic landscape.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/02/14_Overview_1920x900-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) February 19, 2026 [#### VShell and SparkRAT Observed in Exploitation of BeyondTrust Critical Vulnerability (CVE-2026-1731)](https://unit42.paloaltonetworks.com/beyondtrust-cve-2026-1731/) * [Bash](https://unit42.paloaltonetworks.com/tag/bash/ "bash") * [CVE-2026-1731](https://unit42.paloaltonetworks.com/tag/cve-2026-1731/ "CVE-2026-1731") * [PowerShell](https://unit42.paloaltonetworks.com/tag/powershell/ "PowerShell") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/beyondtrust-cve-2026-1731/ "VShell and SparkRAT Observed in Exploitation of BeyondTrust Critical Vulnerability (CVE-2026-1731)") ![](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/02/AdobeStock_1020436911-786x440.jpeg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/07/top-threats.svg)High Profile Threats](https://unit42.paloaltonetworks.com/category/top-cyberthreats/) February 17, 2026 [#### Critical Vulnerabilities in Ivanti EPMM Exploited](https://unit42.paloaltonetworks.com/ivanti-cve-2026-1281-cve-2026-1340/) * [CVE-2026-1281](https://unit42.paloaltonetworks.com/tag/cve-2026-1281/ "CVE-2026-1281") * [CVE-2026-1340](https://unit42.paloaltonetworks.com/tag/cve-2026-1340/ "CVE-2026-1340") * [Ivanti](https://unit42.paloaltonetworks.com/tag/ivanti/ "Ivanti") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/ivanti-cve-2026-1281-cve-2026-1340/ "Critical Vulnerabilities in Ivanti EPMM Exploited") ![Pictorial representation of CVE-2025-0921. Digital illustration of a map of North America with interconnected glowing lines and dots symbolizing network connections across the continent.](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/01/06_Vulnerabilities_1920x900-2-1-786x368.jpg) [![category icon](https://unit42.paloaltonetworks.com/wp-content/uploads/2024/06/icon-threat-research.svg)Threat Research](https://unit42.paloaltonetworks.com/category/threat-research/) January 30, 2026 [#### Privileged File System Vulnerability Present in a SCADA System](https://unit42.paloaltonetworks.com/iconics-suite-cve-2025-0921/) * [CVE-2025-0921](https://unit42.paloaltonetworks.com/tag/cve-2025-0921/ "CVE-2025-0921") * [Privilege escalation](https://unit42.paloaltonetworks.com/tag/privilege-escalation/ "privilege escalation") * [SCADA](https://unit42.paloaltonetworks.com/tag/scada/ "SCADA") [Read now ![Right arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/icon-right-arrow-withtail.svg)](https://unit42.paloaltonetworks.com/iconics-suite-cve-2025-0921/ "Privileged File System Vulnerability Present in a SCADA System") * ![Slider arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/slider-arrow-left.svg) * ![Slider arrow](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/slider-arrow-left.svg) ![Close button](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/icons/close-modal.svg) ![Enlarged Image]() ![Newsletter](https://unit42.paloaltonetworks.com/wp-content/uploads/2026/03/unit42-footer-subscribe-desktop.png) ![UNIT 42 Small Logo](https://unit42.paloaltonetworks.com/wp-content/themes/unit42-v6/dist/images/palo-alto-logo-small.svg) Get updates from Unit 42 ## Peace of mind comes from staying ahead of threats. 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