Critical Vulnerabilities in Microsoft and Fortinet Products

Published 04/13/2023

I. Targeted Entities

• Windows and Fortinet systems

II. Introduction

Several critical vulnerabilities were discovered in both Microsoft and Fortinet products, allowing remote and arbitrary code execution.

For both companies, these vulnerabilities can allow an attacker to install programs; view, change, or delete data; or create new accounts with full user rights. User accounts configured with fewer user rights could be less affected than those operating with administrative rights.

III. Background Information

Microsoft has revealed that its April security update included fixes for 97 flaws, one of which was an actively exploited zero-day vulnerability. Microsoft reported seven vulnerabilities as “critical,” the most serious classification available. The types of vulnerabilities described in Microsoft’s advisory are as follows: privilege escalation, security feature bypass, remote code execution, information disclosure, denial of service, and spoofing (Abrams, 2023).

As for the zero-day vulnerability, known as CVE-2023-28252, it is a Windows common log file system driver elevation-of-privileges vulnerability that allows user privileges to be escalated to SYSTEM, the highest privilege in Windows. Microsoft also reported that this vulnerability was observed in the wild before the security updates patched it (MS-ISAC, 2023).

Moreover, a cybersecurity solutions provider, Fortinet, has announced a patch for several high-severity flaws in products such as FortiOS, FortiProxy, FortiSandbox, FortiWeb, FortiClient, and FortiManager. These issues could allow for cross-site scripting attacks, unauthorized API calls, command execution, arbitrary code execution, privilege escalation, and man-in-the-middle attacks. Fortinet also reported a critical missing-authentication vulnerability, tracked as CVE-2022-41331, with a CVSS score of 9.3, in the FortiPresence infrastructure server. This could be exploited by a remote, unauthenticated attacker via crafted authentication requests to access Redis and MongoDB instances (Arghire, 2023).

Affected Microsoft Systems:

• NET Core
• Azure Machine Learning
• Azure Service Connector
• Microsoft Bluetooth Driver
• Microsoft Defender for Endpoint
• Microsoft Dynamics
• Microsoft Dynamics 365 Customer Voice
• Microsoft Edge (Chromium-based)
• Microsoft Graphics Component
• Microsoft Message Queuing
• Microsoft Office
• Microsoft Office Publisher
• Microsoft Office SharePoint
• Microsoft Office Word
• Microsoft PostScript Printer Driver
• Microsoft Printer Drivers
• Microsoft WDAC OLE DB provider for SQL
• Microsoft Windows DNS
• Visual Studio
• Visual Studio Code
• Windows Active Directory
• Windows ALPC
• Windows Ancillary Function Driver for WinSock
• Windows Boot Manager
• Windows Clip Service
• Windows CNG Key Isolation Service
• Windows Common Log File System Driver
• Windows DHCP Server
• Windows Enroll Engine
• Windows Error Reporting
• Windows Group Policy
• Windows Internet Key Exchange (IKE) Protocol
• Windows Kerberos
• Windows Kernel
• Windows Layer 2 Tunneling Protocol
• Windows Lock Screen
• Windows Netlogon
• Windows Network Address Translation (NAT)
• Windows Network File System
• Windows Network Load Balancing
• Windows NTLM
• Windows PGM
• Windows Point-to-Point Protocol over Ethernet (PPPoE)
• Windows Point-to-Point Tunneling Protocol
• Windows Raw Image Extension
• Windows RDP Client
• Windows Registry
• Windows RPC API
• Windows Secure Boot
• Windows Secure Channel
• Windows Secure Socket Tunneling Protocol (SSTP)
• Windows Transport Security Layer (TLS)
• Windows Win32K

Affected Fortinet Systems:

• FortiDDoS-F versions prior to 6.4.1
• FortiDDoS versions prior to 5.7.0
• FortiADC versions prior to 7.2.0
• FortiAnalyzer versions prior to 7.2.2
• FortiManager versions prior to 7.2.2
• FortiAuthenticator versions prior to 6.5.0
• FortiClientMac versions prior to 7.2.0
• FortiClientWindows versions prior to 7.2.0
• FortiOS versions prior to 7.2.4
• FortiNAC-F versions prior to 7.2.0
• FortiNAC versions prior to 9.4.2
• FortiProxy versions prior to 7.2.3
• FortiPresence versions prior to 2.0.0
• FortiSOAR versions prior to 8.0.0
• FortiSandbox versions prior to 4.2.3
• FortiDeceptor versions prior to 4.2.0
• FortiWeb versions prior to 7.2.0
• FortiSIEM versions prior to 6.5.0

VI. CVEs (Common Vulnerabilities and Exposures)

• CVE-2023-28252 – Windows Common Log File System Driver Elevation of Privilege Vulnerability – Elevates privileges to SYSTEM, the highest user privilege level in Windows
• CVE-2022-40679 – FortiADC / FortiDDoS / FortiDDoS-F – Command injection in log & report module: An improper neutralization of special elements used in an OS command vulnerability in FortiADC, FortiDDoS, and FortiDDoS-F may allow an authenticated attacker to execute unauthorized commands via specifically crafted arguments to existing commands.
• CVE-2022-41330 – FortiOS / FortiProxy – Cross-Site Scripting vulnerabilities in the administrative interface: Multiple improper neutralization of input during web page generation (‘Cross-site Scripting’) vulnerabilities in FortiOS & FortiProxy administrative interface may allow an unauthenticated attacker to perform an XSS attack via crafted HTTP or HTTPS GET requests.
• CVE-2022-43952 – FortiADC – Cross-Site Scripting in Fabric Connectors: An improper neutralization of input during web page generation (‘Cross-site Scripting’) vulnerability in FortiADC may allow an authenticated attacker to perform a cross-site scripting attack via crafted HTTP requests.
• CVE-2022-43955 – FortiNAC – FortiWeb – XSS vulnerability in HTML generated attack report files: An improper neutralization of input during web page generation in the FortiWeb web interface may allow an unauthenticated and remote attacker to perform a reflected cross-site scripting attack (XSS) via injecting a malicious payload in log entries used to build the report.
• CVE-2022-30850 – FortiAuthenticator – Reflected XSS in the password reset page: An improper neutralization of script-related HTML tags in a web page vulnerability in FortiAuthenticator may allow a remote unauthenticated attacker to trigger a reflected cross-site scripting (XSS) attack via the “reset-password” page.
• CVE-2023-27995 – FortiSOAR – Server-side Template Injection in playbook execution: An improper neutralization of special elements in a template engine vulnerability in the FortiSOAR management interface may allow a remote, authenticated attacker to execute arbitrary code via a crafted payload.

V. Recommendations

Microsoft Systems:

Apply Microsoft-provided patches or mitigations to vulnerable systems immediately after testing. (M1051: Update Software)

• Safeguard 7.1: Establish and Maintain a Vulnerability Management Process: Establish and maintain a documented vulnerability management process for enterprise assets. Review and update documentation annually, or when significant enterprise changes occur that could impact this Safeguard.
• Safeguard 7.4: Perform Automated Application Patch Management: Apply application updates to enterprise assets through automated patch management on a monthly or more frequent basis.
• Apply the Principle of Least Privilege to all systems and services, and run all software as a non-privileged user (one without administrative rights) to diminish the effects of a successful attack. (M1026: Privileged Account Management)
• Safeguard 4.7: Manage Default Accounts on Enterprise Assets and Software: Manage default accounts on enterprise assets and software, including root, administrator, and other preconfigured vendor accounts. Example implementations can include: disabling default accounts or making them unusable.
• Safeguard 5.4: Restrict Administrator Privileges to Dedicated Administrator Accounts: Restrict administrator privileges to dedicated administrator accounts on enterprise assets. Conduct general computing activities, such as internet browsing, email, and productivity suite use, from the user’s primary, non-privileged account.
• Remind all users not to visit untrusted websites or to follow links/open files from unknown or untrusted sources. (M1017: User Training
• Safeguard 14.1: Establish and Maintain a Security Awareness Program. The purpose of a security awareness program is to educate the enterprise’s workforce on how to interact securely with enterprise assets and data. Conduct training at hire and, at a minimum, annually. Review and update content annually, or when significant enterprise changes occur that could impact this Safeguard.
• Safeguard 14.2: Train Workforce Members to Recognize Social Engineering Attacks: Train workforce members to recognize social engineering attacks, such as phishing, pretexting, and tailgating.
• Use capabilities to prevent suspicious behavioral patterns on endpoint systems. This could include suspicious behavior of processes, files, API calls, etc. (M1040: Behavior Prevention on Endpoint)
• Safeguard 13.2: Deploy a Host-Based Intrusion Detection Solution: Deploy a host-based intrusion detection solution on enterprise assets, where appropriate and/or supported.
• Safeguard 13.7 : Deploy a Host-Based Intrusion Prevention Solution: Deploy a host-based intrusion prevention solution on enterprise assets, where appropriate and/or supported. Example implementations include using an Endpoint Detection and Response (EDR) client or a host-based IPS agent.

Fortinet Systems:

Apply appropriate updates provided by FortiNet to vulnerable systems immediately after appropriate testing. (M1051: Update Software)

• Safeguard 7.1: Establish and Maintain a Vulnerability Management Process: Establish and maintain a documented vulnerability management process for enterprise assets. Review and update documentation annually, or when significant enterprise changes occur that could impact this Safeguard.
• Safeguard 7.2: Establish and Maintain a Remediation Process: Establish and maintain a risk-based remediation strategy documented in a remediation process, with monthly or more frequent reviews.
• Safeguard 7.3: Perform Automated Operating System Patch Management: Perform operating system updates on enterprise assets through automated patch management on a monthly or more frequent basis.
• Safeguard 7.4: Perform Automated Application Patch Management: Perform application updates on enterprise assets through automated patch management on a monthly or more frequent basis.
• Safeguard 7.6: Perform Automated Vulnerability Scans of Externally-Exposed Enterprise Assets: Perform automated vulnerability scans of externally-exposed enterprise assets using a SCAP-compliant vulnerability scanning tool. Perform scans on a monthly or more frequent basis.
• Safeguard 7.7: Remediate Detected Vulnerabilities: Remediate detected vulnerabilities in software through processes and tooling on a monthly or more frequent basis, based on the remediation process.
• Safeguard 12.1: Ensure Network Infrastructure is Up-to-Date. Example implementations include running the latest stable software release and/or using currently supported network-as-a-service (NaaS) offerings. Review software versions monthly or more frequently to verify support.
• Safeguard 18.1: Establish and Maintain a Penetration Testing Program: Establish and maintain a penetration testing program appropriate to the enterprise's size, complexity, and maturity. Penetration testing program characteristics include scope, such as network, web application, Application Programming Interface (API), hosted services, and physical premise controls; frequency; limitations, such as acceptable hours, and excluded attack types; point of contact information; remediation, such as how findings will be routed internally; and retrospective requirements.
• Safeguard 18.2: Perform Periodic External Penetration Tests: Perform periodic external penetration tests based on program requirements, no less than annually. External penetration testing must include enterprise and environmental reconnaissance to detect exploitable information. Penetration testing requires specialized skills and experience and must be conducted through a qualified party. The testing may be a clear box or an opaque box.
• Safeguard 18.3: Remediate Penetration Test Findings: Remediate penetration test findings based on the enterprise’s policy for remediation scope and prioritization.

• Vulnerability scanning is used to find potentially exploitable software vulnerabilities to remediate them. (M1016: Vulnerability Scanning)
  • Safeguard 16.13: Conduct Application Penetration Testing: Conduct application penetration testing. For critical applications, authenticated penetration testing is better suited to finding business logic vulnerabilities than code scanning and automated security testing. Penetration testing relies on the tester's skill to manually manipulate an application as both an authenticated and an unauthenticated user.

• Apply the Principle of Least Privilege to all systems and services. Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack. (M1026: Privileged Account Management)
  • Safeguard 4.7: Manage Default Accounts on Enterprise Assets and Software: Manage default accounts on enterprise assets and software, including root, administrator, and other preconfigured vendor accounts. Example implementations can include: disabling default accounts or making them unusable.
  • Safeguard 5.4: Restrict Administrator Privileges to Dedicated Administrator Accounts: Restrict administrator privileges to dedicated administrator accounts on enterprise assets. Conduct general computing activities, such as internet browsing, email, and productivity suite use, from the user’s primary, non-privileged account.
  • Safeguard 5.5: Establish and Maintain an Inventory of Service Accounts: Establish and maintain an inventory of service accounts. The inventory must, at a minimum, include the department owner, review date, and purpose. Perform service account reviews to validate that all active accounts are authorized, on a recurring schedule at a minimum of quarterly, or more frequently.
  • Safeguard 6.8: Define and Maintain Role-Based Access Control: Define and maintain role-based access control, through determining and documenting the access rights necessary for each role within the enterprise to successfully carry out its assigned duties. Perform access control reviews of enterprise assets to validate that all privileges are authorized, on a recurring schedule at a minimum annually, or more frequently.
• Architect network sections to isolate critical systems, functions, or resources. Use physical and logical segmentation to prevent access to potentially sensitive systems and information. Use a DMZ to contain any internet-facing services that should not be exposed from the internal network. Configure separate virtual private cloud (VPC) instances to isolate critical cloud systems. (M1030: Network Segmentation)
  • Safeguard 12.2: Establish and Maintain a Secure Network Architecture. A secure network architecture must address segmentation, least privilege, and availability, at a minimum.
• Restrict code execution to a virtual environment on or in transit to an endpoint system. (M1048: Application Isolation and Sandboxing)
  • Safeguard 16.8: Separate Production and Non-Production Systems: Maintain separate environments for production and non-production systems.

• Use capabilities to detect and block conditions that may lead to or be indicative of a software exploit occurring. (M1050: Exploit Protection)
  • Safeguard 10.5: Enable Anti-Exploitation Features: Enable anti-exploitation features on enterprise assets and software, where possible, such as Microsoft® Data Execution Prevention (DEP), Windows® Defender Exploit Guard (WDEG), or Apple® System Integrity Protection (SIP) and Gatekeeper™.
• Restrict use of certain websites, block downloads/attachments, block JavaScript, restrict browser extensions, etc. (M1021: Restrict Web-Based Content)
  • Safeguard 9.2: Use DNS Filtering Services: Use DNS filtering services on all enterprise assets to block access to known malicious domains.
  • Safeguard 9.3: Maintain and Enforce Network-Based URL Filters: Enforce and update network-based URL filters to prevent enterprise assets from connecting to potentially malicious or unapproved websites. Example implementations include category-based filtering, reputation-based filtering, and block lists. Enforce filters for all enterprise assets.
  • Safeguard 9.6: Block Unnecessary File Types: Block unnecessary file types attempting to enter the enterprise’s email gateway.

• Inform and educate users about the threats posed by hypertext links in emails or attachments, especially from untrusted sources. Remind users not to visit untrusted websites or follow links from unknown or untrusted sources. (M1017: User Training)
  • Safeguard 14.1: Establish and Maintain a Security Awareness Program. The purpose of a security awareness program is to educate the enterprise’s workforce on how to interact with enterprise assets and data securely. Conduct training at hire and, at a minimum, annually. Review and update content annually, or when significant enterprise changes occur that could impact this Safeguard.
  • Safeguard 14.2: Train Workforce Members to Recognize Social Engineering Attacks: Train workforce members to recognize social engineering attacks, such as phishing, pretexting, and tailgating.

VII. References

Arghire, I. (2023, April 12). Fortinet Patches Critical Vulnerability in Data Analytics Solution. SecurityWeek. Retrieved April 12, 2023, from https://www.securityweek.com/fortinet-patches-critical-vulnerability-in-data-analytics-solution/

Abrams, L. (2023, April 11). Microsoft April 2023 Patch Tuesday Fixes 1 Zero-day, 97 Flaws. BleepingComputer. Retrieved April 12, 2023, from https://www.bleepingcomputer.com/news/microsoft/microsoft-april-2023-patch-tuesday-fixes-1-zero-day-97-flaws/

MS-ISAC. (2023, April 11). MS-ISAC CYBERSECURITY ADVISORY – Critical Patches Issued for Microsoft Products April 11, 2023 – PATCH NOW – TLP: CLEAR

MS-ISAC. (2023, April 12). MS-ISAC CYBERSECURITY ADVISORY – Multiple Vulnerabilities in Fortinet Products Could Allow for Arbitrary Code Execution – PATCH NOW – TLP: CLEAR

Security Analysts: Sreten Dedic