CVE-2019-9197 in Unity Editor
Summary
by MITRE
The com.unity3d.kharma protocol handler in Unity Editor 2018.3 allows remote attackers to execute arbitrary code.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 01/01/2020
The vulnerability identified as CVE-2019-9197 resides within the com.unity3d.kharma protocol handler component of Unity Editor version 2018.3, representing a critical remote code execution flaw that exposes systems to unauthorized command execution. This protocol handler mechanism is designed to facilitate communication between Unity Editor and external applications through a specific URI scheme, but it fails to properly validate input parameters, creating a pathway for malicious actors to inject and execute arbitrary code on affected systems. The flaw exists in the way the protocol handler processes incoming URI requests, particularly when handling specially crafted URLs that contain malicious payloads. Attackers can leverage this vulnerability by crafting deceptive web pages or sending malicious links that, when clicked, trigger the vulnerable protocol handler and execute commands with the privileges of the user running Unity Editor.
The technical implementation of this vulnerability stems from inadequate input sanitization and validation within the Unity Editor's protocol handler architecture. When a user clicks on a malicious URI that begins with com.unity3d.kharma, the editor attempts to process the request without sufficient validation of the parameters passed through the URL. This lack of proper parameter filtering allows attackers to inject command-line arguments that get executed by the underlying system shell, effectively bypassing normal security boundaries. The vulnerability is classified as a command injection flaw that aligns with CWE-77 and CWE-94, which specifically address improper neutralization of special elements used in OS commands and improper control of generation of code. The protocol handler's failure to properly escape or validate input parameters creates a direct pathway for arbitrary code execution, potentially allowing attackers to perform actions such as file manipulation, system reconnaissance, or privilege escalation depending on the user context.
The operational impact of CVE-2019-9197 extends beyond simple code execution, as it represents a significant threat vector for attackers targeting developers and organizations using Unity Editor for game development or application creation. Since Unity Editor is commonly installed on developer workstations and development servers, the vulnerability can be exploited through social engineering techniques such as phishing emails, malicious websites, or compromised web applications that redirect users to crafted URLs. The attack surface is particularly concerning in enterprise environments where developers may have elevated privileges or access to sensitive development resources. Successful exploitation can lead to complete system compromise, data theft, or the installation of persistent backdoors. The vulnerability also aligns with ATT&CK technique T1059.001 for command and script interpreter, specifically focusing on the execution of malicious code through system shells, and T1068 for exploit for privilege escalation, as attackers may leverage the initial code execution to gain higher system privileges.
Organizations and developers should immediately implement mitigation strategies to address CVE-2019-9197, beginning with the immediate upgrade to Unity Editor version 2018.3.10f1 or later, which includes patches specifically addressing this vulnerability. System administrators should also consider implementing security policies that restrict protocol handler registrations and disable unnecessary URI schemes that could be exploited. Network-level protections such as web application firewalls and URL filtering systems can help prevent users from accessing malicious URLs that trigger the vulnerable protocol handler. Additionally, user education and awareness programs should emphasize the dangers of clicking unknown links or visiting untrusted websites, as the vulnerability relies heavily on social engineering for initial compromise. Security monitoring should include detection of suspicious protocol handler usage patterns and unusual command execution activities on systems running Unity Editor. The vulnerability demonstrates the critical importance of proper input validation in application components and the potential consequences of insufficient security controls in development tools that are frequently used in enterprise environments.