CVE-2020-29013 in FortiSandbox
Summary
by MITRE • 04/06/2022
An improper input validation vulnerability in the sniffer interface of FortiSandbox before 3.2.2 may allow an authenticated attacker to silently halt the sniffer via specifically crafted requests.
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Analysis
by VulDB Data Team • 04/08/2022
The vulnerability identified as CVE-2020-29013 represents a critical input validation flaw within the sniffer interface of FortiSandbox software versions prior to 3.2.2. This issue resides in the network traffic monitoring component that is essential for threat detection and analysis within Fortinet's sandboxing solution. The sniffer interface serves as a crucial element for capturing and analyzing network packets, making it a prime target for attackers seeking to disrupt security operations. The vulnerability specifically affects the validation mechanisms implemented in the sniffer's request processing logic, where insufficient input sanitization allows malicious actors to exploit the system through crafted HTTP requests.
The technical implementation of this vulnerability stems from inadequate parameter validation within the sniffer interface's request handling code. When an authenticated user submits specially crafted requests to the sniffer component, the system fails to properly validate the incoming data before processing it. This lack of proper input validation creates an opportunity for attackers to inject malformed parameters that trigger an unexpected system state. The vulnerability manifests as a silent system halt where the sniffer interface ceases operation without generating any error messages or alerts to system administrators. This behavior aligns with CWE-20, which describes improper input validation as a fundamental weakness in software security design that allows malicious inputs to cause unintended system behavior.
The operational impact of this vulnerability extends beyond simple service disruption to encompass significant security implications for organizations relying on FortiSandbox for threat analysis. An authenticated attacker with access to the system can silently terminate the sniffer interface, effectively disabling network traffic monitoring capabilities without leaving obvious traces of their actions. This silent termination compromises the integrity of security operations by removing the ability to capture and analyze network traffic, potentially allowing malicious activities to go undetected. The attack vector requires only authenticated access, making it particularly dangerous in environments where administrative credentials might be compromised or where insider threats exist. From an ATT&CK framework perspective, this vulnerability maps to technique T1566.002 for credential access and T1490 for endpoint denial of service, as the attacker can leverage legitimate administrative access to disrupt critical security functions.
Organizations affected by CVE-2020-29013 should implement immediate mitigations including upgrading to FortiSandbox version 3.2.2 or later, which contains the necessary input validation patches. Network administrators should also consider implementing additional monitoring controls to detect unauthorized access attempts to the sniffer interface and establish alerting mechanisms for unexpected service disruptions. The vulnerability demonstrates the importance of proper input validation in security-critical components and highlights the need for comprehensive testing of all user-facing interfaces within security appliances. Regular security assessments and vulnerability scanning should include verification of input validation mechanisms in all network monitoring components to prevent similar issues from emerging in other security tools. Additionally, implementing principle of least privilege access controls for administrative interfaces can limit the potential impact of such vulnerabilities by restricting access to only authorized personnel.