We’re thrilled to announce significant enhancements to the Notus Scanner in both our Greenbone Enterprise and Community Edition vulnerability scanners. As a core component of the OpenVAS scanner, Notus Scanner is Greenbone’s module for performing Local Security Checks (LSC) and supports our industry leading detection capabilities by detecting vulnerable software packages and libraries directly on endpoints. This vital tool has been integral in safeguarding software used on a wide array of popular Linux distributions, including Debian, Ubuntu, OpenSUSE, Red Hat Enterprise Linux (RHEL) and Fedora, among others.

Expanding Horizons with Huawei

In our efforts to expand our service scope and enhance security, Notus Scanner is now extending its capabilities to include Linux distributions maintained by Huawei. This update will introduce vulnerable package detection for Huawei’s Versatile Routing Platform (VRP) products, EulerOS, EulerOS Virtual, Huawei Cloud EulerOS (HCE) and openEuler. These additions are aimed at fortifying security measures for all organizations that implement Huawei technologies, thereby strengthening Greenbone’s protective reach.

For users of our Greenbone Enterprise appliances, we are pleased to introduce the inclusion of Huawei Cloud EulerOS (HCE) in our vulnerability feed, ensuring that enterprises utilizing cloud infrastructure can benefit from our expanded detection capabilities.

Community Edition Detection just Got Stronger

The Greenbone Community Edition now boasts enhanced detection capabilities with the integration of Huawei’s EulerOS, EulerOS Virtual and openEuler into the vulnerability feed. This update widens the scope of our free and open source security coverage, and ensures that a more diverse set of software products can be secured by our Community Edition users. This enhancement reaffirms our commitment to providing comprehensive security solutions and democratizing cybersecurity capabilities.

High Performance and Reliability with Rust

Earlier in 2024, we released a new, high-performance Rust-based version of the Notus Scanner. This advancement underscores our commitment to providing not only extensive coverage but also efficient and reliable scanning capabilities. Rust’s safety features significantly reduce the risk of common bugs, enhancing stability and performance in our scanning processes.

Local Security Checks Are Essential

Unlike network vulnerability tests that scan a host’s network attack surface (such as active services accessible via network interfaces), Local Security Checks delve into the host’s attack surface at the software level. By scanning software installed on the host device directly for known vulnerabilities, a thorough assessment of potential security risks is assured.

Summary

We at Greenbone are excited about the addition of Huawei maintained Linux updates and confident in their ability to provide our users with even better tools to protect their digital environments. The expansion of Notus Scanner’s capabilities is more than just a technical enhancement – it’s a commitment to our users’ security. By broadening our scanning spectrum to include more Linux distributions, we support more products and ensure better cybersecurity for all.

For more information on how these updates can benefit your organization, or to learn more about our full suite of security solutions, please contact our sales team directly, get a 14 day free trial of our entry-level Enterprise product Greenbone Basic or jump right in and order Greenbone Basic today. Let us help you strengthen your defenses and stay ahead of potential threats!

In 2024, geopolitical instability, marked by conflicts in Ukraine and the Middle East, emphasized the need for stronger cybersecurity in both the public and private sector. China targeted U.S. defense, utilities, internet providers and transportation, while Russia launched coordinated cyberattacks on U.S. and European nations, seeking to influence public opinion and create discord among Western allies over the Ukrainian war. As 2024 ends, we can look back at a hectic cybersecurity landscape on the edge.

2024 marked another record setting year for CVE (Common Vulnerabilities and Exposures) disclosures. Even if many are so-called “AI Slop” reports [1][2], the sheer volume of published vulnerabilities creates a big haystack. As IT security teams seek to find high-risk needles in a larger haystack, the chance of oversight becomes more prevalent. 2024 was also a record year for ransomware payouts in terms of volume and size, and Denial of Service (DoS) attacks.

It also saw the NIST NVD outage, which affected many organizations around the world including security providers. Greenbone’s CVE scanner is a CPE (Common Platform Enumeration) matching function and has been affected by the NIST NVD outage. However, Greenbone’s primary scanning engine, OpenVAS Scanner, is unaffected. OpenVAS actively interacts directly with services and applications, allowing Greenbone’s engineers to build reliable vulnerability tests using the details from initial CVE reports.

In 2025, fortune will favor organizations that are prepared. Attackers are weaponizing cyber-intelligence faster; average time-to-exploit (TTE) is mere days, even hours. The rise of AI will create new challenges for cybersecurity. Alongside these advancements, traditional threats remain critical for cloud security and software supply chains. Security analysts predict that fundamental networking devices such as VPN gateways, firewalls and other edge devices will continue to be a hot target in 2025.

In this edition of our monthly Threat Report, we review the most pressing vulnerabilities and active exploitation campaigns that emerged in December 2024.

Mitel MiCollab: Zero-Day to Actively Exploited in a Flash

Once vulnerabilities are published, attackers are jumping on them with increased speed. Some vulnerabilities have public proof of concept (PoC) exploit code within hours, leaving defenders with minimal reaction time. In early December, researchers at GreyNoise observed exploitation of Mitel MiCollab the same day that PoC code was published. Mitel MiCollab combines voice, video, messaging, presence and conferencing into one platform. The new vulnerabilities have drawn alerts from the Belgian national Center for Cybersecurity, the Australian Signals Directorate (ASD) and the UK’s National Health Service (NHS) in addition to the American CISA (Cybersecurity and Infrastructure Security Agency). Patching the recent vulnerabilities in MiCollab is considered urgent.

Here are details about the new actively exploited CVEs in Mitel MiCollab:

  • CVE-2024-41713 (CVSS 7.8 High): A path traversal vulnerability in the NuPoint Unified Messaging (NPM) component of Mitel MiCollab allows unauthenticated path traversal by leveraging the “…/” technique in HTTP requests. Exploitation can expose highly sensitive files.
  • CVE-2024-35286 (CVSS 10 Critical): A SQL injection vulnerability has been identified in the NPM component of Mitel MiCollab which could allow a malicious actor to conduct a SQL injection attack.

Since mid-2022, CISA has tracked three additional actively exploited CVEs in Mitel products which are known to be leveraged in ransomware attacks. Greenbone is able to detect endpoints vulnerable to these high severity CVEs with active checks [4][5].

Array Networks SSL VPNs Exploited by Ransomware

CVE-2023-28461 (CVSS 9.8 Critical) is a Remote Code Execution (RCE) vulnerability in Array Networks Array AG Series and vxAG SSL VPN appliances. The devices, touted by the vendor as a preventative measure against ransomware, are now being actively exploited in recent ransomware attacks. Array Networks themselves were breached by the Dark Angels ransomware gang earlier this year [1][2].

According to recent reports, Array Networks holds a significant market share in the Application Delivery Controller (ADC) market. According to the ​​IDC’s WW Quarterly Ethernet Switch Tracker, they are the market leader in India, with a market share of 34.2%. Array Networks has released patches for affected products running ArrayOS AG 9.4.0.481 and earlier versions. The Greenbone Enterprise Feed has included a detection test for CVE-2023-28461 since it was disclosed in late March 2023.

CVE-2024-11667 in Zyxel Firewalls

CVE-2024-11667 (CVSS 9.8 Critical) in Zyxel firewall appliances are being actively exploited in ongoing ransomware attacks. A directory traversal vulnerability in the web management interface could allow an attacker to download or upload files via a maliciously crafted URL. Zyxel Communications is a Taiwanese company specializing in designing and manufacturing networking devices for businesses, service providers and consumers. Reports put Zyxel’s market share at roughly 4.2% of the ICT industry with a diverse global footprint including large Fortune 500 companies.

A defense in depth approach to cybersecurity is especially important in cases such as this. When attackers compromise a networking device such as a firewall, typically they are not immediately granted access to highly sensitive data. However, initial access allows attackers to monitor network traffic and enumerate the victim’s network in search of high value targets.

Zyxel advises updating your device to the latest firmware, temporarily disabling remote access if updates cannot be applied immediately and applying their best practices for securing distributed networks. CVE-2024-11667 affects Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38 and USG20(W)-VPN series firmware versions V5.10 through V5.38. Greenbone can detect the vulnerability CVE-2024-11667 across all affected products.

Critical Flaws in Apache Struts 2

CVE-2024-53677 (CVSS 9.8 Critical), an unrestricted file upload [CWE-434] flaw affecting Apache Struts 2 allows attackers to upload executable files into web-root directories. If a web-shell is uploaded, the flaw may lead to unauthorized Remote Code Execution. Apache Struts is an open-source Java-based web-application framework widely used by the public and private sectors including government agencies, financial institutions and other large organizations [1]. Proof of concept (PoC) exploit code is publicly available, and CVE-2024-53677 is being actively exploited increasing its risk.

The vulnerability was originally tracked as CVE-2023-50164, published in December 2023 [2][3]. However, similarly to a recent flaw in VMware vCenter, the original patch was ineffective resulting in the re-emergence of vulnerability. CVE-2024-53677 affects the FileUploadInterceptor component and thus, applications not using this module are unaffected. Users should update their Struts2 instance to version 6.4.0 or higher and migrate to the new file upload mechanism. Other new critical CVEs in popular open-source software (OSS) from Apache:

The Apache Software Foundation (ASF) follows a structured process across its projects that encourages private reporting and releasing patches prior to public disclosure so patches are available for all CVEs mentioned above. Greenbone is able to detect systems vulnerable to CVE-2024-53677 and other recently disclosed vulnerabilities in ASF Foundation products.

Palo Alto’s Secure DNS Actively Exploited for DoS

CVE-2024-3393 (CVSS 8.7 High) is a DoS (Denial of Service) vulnerability in the DNS Security feature of PAN-OS. The flaw allows an unauthenticated attacker to reboot PA-Series firewalls, VM-Series firewalls, CN-Series firewalls and Prisma Access devices via malicious packets sent through the data plane. By repeatedly triggering this condition, attackers can cause the firewall to enter maintenance mode. CISA has identified CVE-2024-3393 vulnerability as actively exploited and it’s among five other actively exploited vulnerabilities in Palo Alto’s products over only the past two months.

According to the advisory posted by Palo Alto, only devices with a DNS Security License or Advanced DNS Security License and logging enabled are affected. It would be an easy assumption to say that these conditions mean that top-tier enterprise customers are affected. Greenbone is able to detect the presence of devices affected by CVE-2024-3393 with a version detection test.

Microsoft Security in 2024: Who Left the Windows Open?

While it would be unfair to single out Microsoft for providing vulnerable software in 2024, the Redmond BigTech certainly didn’t beat security expectations. A total of 1,119 CVEs were disclosed in Microsoft products in 2024; 53 achieved critical severity (CVSS > 9.0), 43 were added to CISA’s Known Exploited Vulnerabilities (KEV) catalog, and at least four were known vectors for ransomware attacks. Although the comparison is rough, the Linux kernel saw more (3,148) new CVEs but only three were rated critical severity and only three were added to CISA KEV. Here are the details of the new actively exploited CVEs in Microsoft Windows:

  • CVE-2024-35250 (CVSS 7.8 High): A privilege escalation flaw allowing an attacker with local access to a system to gain system-level privileges. The vulnerability was discovered in April 2024, and PoC exploit code appeared online in October.
  • CVE-2024-49138 (CVSS 7.8 High): A heap-based buffer overflow [CWE-122] privilege escalation vulnerability; this time in the Microsoft Windows Common Log File System (CLFS) driver. Although no publicly available exploit exists, security researchers have evidence that this vulnerability can be exploited by crafting a malicious CLFS log to execute privileged commands at the system privilege level.

Detection and mitigation of these new Windows CVEs is critical since they are actively under attack. Both were patched in Microsoft’s December patch release. Greenbone is able to detect CVE-2024-35250 and CVE-2024-49138 as well as all other Microsoft vulnerabilities published as CVEs.

Summary

2024 highlighted the continuously challenging cybersecurity landscape with record-setting vulnerability disclosures, ransomware payouts, DoS attacks and an alarming rise in active exploitations. The rapid weaponization of vulnerabilities emphasizes the need for a continuous vulnerability management strategy and a defense-in-depth approach.

December saw new critical flaws in Mitel, Apache and Microsoft products. More network products: Array Networks VPNs and Zyxel firewalls are now being exploited by ransomware threat actors underscoring the urgency for proactive patching and robust detection measures. As we enter 2025, fortune will favor those prepared; organizations must stay vigilant to mitigate risks in an increasingly hostile cyber landscape.

An actively exploited RCE (Remote Code Execution) with system privileges vulnerability that does not require user-interaction is as bad as it gets from a technical standpoint. When that CVE impacts software widely used by Fortune 500 companies, it is a ticking time bomb. And when advanced persistent threat actors jump on a software vulnerability such as this, remediation needs to become an emergency response effort. Most recently, CVE-2024-50623 (also now tracked as CVE-2024-55956) affecting more than 4,200 users of Cleo’s MFT (Managed File Transfer) software met all these prerequisites for disaster. It has been implicated in active ransomware campaigns affecting several Fortune 500 companies taking center stage in cybersecurity news.

In this cybersecurity alert, we provide a timeline of events related to CVE-2024-50623 and CVE-2024-55956 and associated ransomware campaigns. Even if you are not using an affected product, this will give you valuable insight into the vulnerability lifecycle and the risks of third-party software supply chains. 

CVE-2024-50623 and CVE-2024-55956: a Timeline of Events

The vulnerability lifecycle is complex. You can review our previous article about next-gen vulnerability management for an in depth explanation on how this process happens. In this report, we will provide a timeline for the disclosure and resolution of CVE-2024-50623 and subsequently CVE-2024-55956 as a failed patch attempt from the software vendor Cleo was uncovered and exploited by ransomware operators. Our Greenbone Enterprise Feed includes detection modules for both CVEs [1][2], allowing organizations to identify vulnerable systems and apply emergency remediation. Here is a timeline of events so far:

  • October 28, 2024: CVE-2024-50623 (CVSS 10 Critical) affecting several Cleo MFT products was published by the vendor and a patched version 5.8.0.21 was
  • November 2024: CVE-2024-50623 was exploited for data exfiltration impacting at least 10 organizations globally including Blue Yonder, a supply chain management service used by Fortune 500 companies.
  • December 3, 2024: Security researchers at Huntress identified active exploitation of CVE-2024-50623 capable of bypassing the original patch (version 5.8.0.21).
  • December 8, 2024: Huntress observed a significant uptick in the rate of exploitation. This could be explained by the exploit code being sold in a Malware as a Service cyber crime business model or simply that the attackers had finished reconnaissance and launched a widespread campaign for maximum impact.
  • December 9, 2024: Active exploitation and proof-of-concept (PoC) exploit code was reported to the software vendor Cleo.
  • December 10, 2024: Cleo released a statement acknowledging the exploitability of their products despite security patches and issued additional mitigation guidance.
  • December 11, 2024: Wachtowr Labs released a detailed technical report describing how CVE-2024-50623 allows RCE via Arbitrary File Write [CWE-434]. Cleo updated their mitigation guidance and released a subsequent patch (version 5.8.0.24).
  • December 13, 2024: A new name, CVE-2024-55956 (CVSS 10 Critical), was issued for tracking this ongoing vulnerability, and CISA added the flaw to its Known Exploited Vulnerabilities (KEV) catalog, flagged for use in ransomware attacks.

Cleo Products Leveraged in Ransomware Attacks

The risk to global business posed by CVE-2024-50623 and CVE-2024-55956 is high. These two CVEs potentially impact more than 4,200 customers of Cleo LexiCom, a desktop-based client for communication with major trading networks, Cleo VLTrader, a server-level solution tailored for mid-enterprise organizations, and Cleo Harmony for large enterprises.

The CVEs have been used as initial access vectors in a recent ransomware campaign. The Termite ransomware operation [1][2] has been implicated in the exploitation of Blue Yonder, a Panasonic subsidiary in November 2024. Blue Yonder is a supply chain management platform used by large tech companies including Microsoft, Lenovo, and Western Digital, and roughly 3,000 other global enterprises across many industries; Bayer, DHL, and 7-Eleven to name a few. Downtime of Blue Yonder’s hosted service caused payroll disruptions for StarBucks. The Clop ransomware group has also claimed responsibility for recent successful ransomware attacks.

In the second stage of some breaches, attackers conducted Active Directory domain enumeration [DS0026], installed web-shells [T1505.003] for persistence [TA0003], and attempted to exfiltrate data [TA0010] from the victim’s network after gaining initial access via RCE. An in-depth technical description of the Termite ransomware’s architecture is also available.

Mitigating CVE-2024-50623 and CVE-2024-55956

Instances of Cleo products version 5.8.0.21 are still vulnerable to cyber attacks. The most recent patch, version 5.8.0.24 is required to mitigate exploitation. All users are urged to apply updates with urgency. Additional mitigation and best practices include disabling the autorun functionality in Cleo products, removing access from the Internet or using firewall rules to restrict access to only authorized IP addresses, and blocking the IP addresses of endpoints implicated in the attacks.

Summary

Cleo Harmony, VLTrader, and LexiCom prior to version 5.8.0.24 are under active exploitation due to critical RCE vulnerabilities (CVE-2024-50623 and CVE-2024-55956). These flaws have been the entry point for successful ransomware attacks against at least 10 organizations and impacting Fortune 500 companies. Greenbone provides detection for affected products and affected users are urged to apply patches and implement mitigation strategies, as attackers will certainly continue to leverage these exploits.

Web browsers are a primary gateway to business and consequently they are also a primary gateway for cyber attacks. Malware targeting browsers could gain direct unauthorized access to a target’s network and data or social engineer victims into providing sensitive information that gives the attacker unauthorized access, such as account credentials. In 2024, major browsers (Chrome, Firefox, and Safari) accounted for 59 Critical severity (CVSS3 ³ 9) and 256 High severity (CVSS3 between 7.0 and 8.9) vulnerabilities. 10 CVEs (Common Vulnerabilities and Exposures) in the trifecta were added to the KEV (Known Exploited Vulnerabilities) catalog of CISA (Cybersecurity & Infrastructure Security Agency). Browser security should therefore be top-of-mind for security teams.

In light of this, we are proud to announce the addition of CIS Google Chrome Benchmark v3.0.0 Level 1 auditing to our list of compliance capabilities. This latest feature allows our Enterprise feed subscribers to verify their Google Chrome configurations against the industry-leading CIS compliance framework of the CIS (Center for Internet Security). The new Google Chrome benchmark tests will sit among our other CIS controls in critical cybersecurity areas such as Apache, IIS, NGINX, MongoDB, Oracle, PostgreSQL, Windows and Linux [1] [2].

CIS Google Chrome Benchmark for Windows

The CIS Google Chrome Benchmark v3.0.0 Level 1 is now available in the Greenbone Enterprise Feed. It establishes a hardened configuration for the Chrome browser. For Windows, implementing the controls involves setting Windows registry keys to define Chrome’s security configuration. Continuous attestation is important because if modified at the user level Chrome becomes more vulnerable to data-leakage, social engineering attacks or other attack vectors.

Our Enterprise vulnerability feed uses compliance policies to run tests on target endpoints, verifying each requirement in the CIS benchmark through one or more dedicated vulnerability tests. These tests are grouped into scan configurations which can be used to create scan tasks that access groups of target systems to verify their security posture. When aligning with internal risk requirements or mandatory government policies, Greenbone has you covered.

The Importance of Browser Security

Much of the critical information flowing through the average organization is transmitted through the browser. The rise of a remote workforce and cloud-based web-applications means that web browsers are a primary interface for business activities. Not surprisingly, in the past few years, Internet browsers have been a hotbed for exploitation. National cybersecurity agencies such Germany’s BSI [3] [4], CISA [5] [6], and the Canadian Centre for Cyber Security [7] have all released advisories for addressing the risks posed by Internet browsers.

Browsers can be exploited via technical vulnerabilities and misconfigurations that could lead to remote code execution, theft of sensitive data and account takeover, but are also a conduit for social engineering attacks. Browser security must be addressed by implementing a hardened security profile and continuously attesting it and by regularly applying updates to combat any recently discovered vulnerabilities. Greenbone is able to detect known vulnerabilities for published CVEs in all major browsers and now with our latest CIS Google Chrome Benchmark certification, we can attest industry standard browser compliance.

How Does the CIS Google Chrome Benchmark Improve Browser Security?

Every CIS Benchmark is developed through a consensus review process that involves a global community of subject matter experts from diverse fields such as consulting, software development, auditing, compliance, security research, operations, government, and legal. This collaborative process is meant to ensure that the benchmarks are practical and data-driven and reflect real-world expertise. As such, CIS Benchmarks serve as a vital part of a robust cybersecurity program.

In general, CIS Benchmarks focus on secure technical configuration settings and should be used alongside essential cyber hygiene practices, such as monitoring and promptly patching vulnerabilities in operating systems, applications and libraries.

The CIS Google Chrome Benchmark defines security controls such as:

  • No domains can bypass scanning for dangerous resources such as phishing content and malware.
  • Strict verification of SSL/TLS certificates issued by websites.
  • Reducing Chrome’s overall attack surface by ensuring the latest updates are automatically applied periodically.
  • Chrome is configured to detect DNS interception which could potentially allow DNS hijacking.
  • Chrome and extensions cannot interact with other third party software.
  • Websites and browser extensions cannot abuse connections with media, the local file system or external devices such as Bluetooth, USB or media casting devices.
  • Only extensions from the Google Chrome Web Store can be installed.
  • All processes forked from the main Chrome process are stopped once the Chrome application has been closed.
  • SafeSites content filtering blocks links to adult content from search results.
  • Prevent importing insecure data such as auto-fill form data, default homepage or other configuration settings.
  • Ensuring that critical warnings cannot be suppressed.

Greenbone Is a CIS Consortium Member

As a member of the CIS consortium, Greenbone continues to enhance its CIS Benchmark scan configurations. All our CIS Benchmarks policies are aligned with CIS hardening guidelines and certified by CIS, ensuring maximum security for system audits. Also, Greenbone has added a new compliance view to the Greenbone Security Assistant (GSA) web-interface, streamlining the process for organizations seeking to remove security gaps from their infrastructure to prevent security breaches.

Summary

CIS Controls are critical for safeguarding systems and data by providing clear, actionable guidance on secure configurations. The CIS Google Chrome Benchmark is especially vital at the enterprise level, where browsers impact many forms of sensitive data. It’s exciting to announce that Greenbone is expanding the industry leading vulnerability detection capabilities with a new compliance scan: the CIS Google Chrome Benchmark v3.0.0 Level 1. With this certification, Greenbone continues to strengthen its position as a trusted ally in proactive cybersecurity. This latest feature reflects our dedication to advancing IT security and protecting against evolving cyber threats.