CVE-2025-34393: Insecure Reflection in Barracuda Service Center Leads to Critical Remote Code Execution

A critical vulnerability, identified as CVE-2025-34393, has been discovered in Barracuda’s Remote Monitoring and Management (RMM) solution. This flaw, present in versions of Barracuda Service Center prior to 2025.1.1, opens the door for attackers to achieve remote code execution (RCE) on vulnerable systems. Discovered by Piotr Bazydlo of watchTowr and publicly disclosed on December 10, 2025, this vulnerability stems from a fundamental weakness in how the Service Center handles WSDL service names.

Key aspects of the vulnerability:

Attack Mechanism: The core of CVE-2025-34393 lies in the Barracuda Service Center’s improper validation of an attacker-controlled WSDL service name. This lack of proper validation allows for “insecure reflection,” a programming concept where a program can inspect and manipulate its own structure and behavior at runtime. In this context, an attacker can leverage this vulnerability to:

• Invoke Arbitrary Methods: By manipulating the WSDL service name, an attacker can trick the Service Center into executing unintended methods within the application.
• Deserialize Untrusted Types: The vulnerability also allows for the deserialization of untrusted data, designated as CVE-2025-34394, effectively enabling an attacker to inject malicious objects into the application’s memory and gain control. The Barracuda Service Center, a component of the RMM solution, exposes a .NET Remoting service. This service is insufficiently protected against the deserialization of untrusted data. An attacker can exploit this by sending specially crafted serialized data to the .NET Remoting endpoint.

Impact: Successful exploitation of CVE-2025-34393 can lead to a complete compromise of the affected system. An attacker can gain the ability to execute arbitrary code remotely, potentially leading to data theft, system disruption, or further network lateral movement.

How bad is this?

According to various security advisories and databases, including VulnCheck and dbugs, CVE-2025-34393 carries a CVSS v4.0 Base Score of 10.0 (CRITICAL). This high score reflects the severity and ease of exploitation.

• Severity: Critical
• Domain Access Required: Not explicitly stated as a prerequisite for initial exploitation, but the potential impact on an RMM solution implies broad access.
• Trivial Exploitation: The vulnerability is described as having trivial exploitation due to the lack of complex prerequisites for the attacker.

Who is affected by this?

The following software is affected by CVE-2025-34393:

• Barracuda Service Center versions prior to 2025.1.1

This vulnerability specifically impacts organizations utilizing Barracuda’s RMM solution for managing their IT infrastructure.

How is it exploited?

This vulnerability is exploitable remotely. An attacker can craft a malicious WSDL service request that targets the Barracuda Service Center. By sending this crafted request, the attacker can abuse the insecure reflection mechanism to achieve remote code execution. No prior authentication is explicitly stated as required for exploitation, making it a particularly dangerous threat.

How do I protect myself?

Barracuda has released a patch to address this vulnerability.

• Update Barracuda Service Center to version 2025.1.1 or later. This is the most crucial step in mitigating the risk associated with CVE-2025-34393.

Organizations should consult Barracuda’s official advisories and product documentation for specific instructions on applying the update.

Mitigating factors?

While no specific mitigating factors are highlighted beyond patching, the inherent nature of RMM solutions means that securing the Service Center is paramount. Proper network segmentation and access controls for the RMM infrastructure can further limit the potential impact should an exploit occur on an unpatched system. However, the primary and most effective defense is the immediate application of the security update.

Additional Resources:

• VulnCheck Advisory: https://www.vulncheck.com/advisories/barracuda-rmm-service-center-insecure-reflection-rce
• NVD (National Vulnerability Database): https://nvd.nist.gov/vuln/detail/CVE-2025-34393
• Barracuda RMM Product Page: https://www.barracuda.com/products/msp/network-protection/rmm
• Barracuda RMM Release Notes 2025.1.1: https://download.mw-rmm.barracudamsp.com/PDF/2025.1.1/RN_BRMM_2025.1.1_EN.pdf