CVE-2023-4957 in ZTC ZT410-203dpi ZPL Printer
Summary
by MITRE • 10/25/2023
A vulnerability of authentication bypass has been found on a Zebra Technologies ZTC ZT410-203dpi ZPL printer. This vulnerability allows an attacker that is in the same network as the printer, to change the username and password for the Web Page by sending a specially crafted POST request to the setvarsResults.cgi file. For this vulnerability to be exploitable, the printers protected mode must be disabled.
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Analysis
by VulDB Data Team • 08/28/2025
The vulnerability identified as CVE-2023-4957 represents a critical authentication bypass flaw within Zebra Technologies ZTC ZT410-203dpi ZPL printers that operates at the application layer of the network stack. This weakness specifically targets the web-based management interface of the device and stems from inadequate input validation and insufficient authentication mechanisms. The vulnerability is particularly concerning because it can be exploited by attackers who are already within the same network segment, eliminating the need for external access or complex reconnaissance phases. The affected device employs a web server component that processes configuration changes through the setvarsResults.cgi script, which fails to properly verify the legitimacy of incoming requests. This authentication bypass vulnerability directly maps to CWE-287 which addresses improper authentication issues in software systems. The attack vector requires an attacker to be in the same local network segment as the target printer, which aligns with the concept of lateral movement in the MITRE ATT&CK framework under the technique of "Network Service Scanning" and subsequent "Exploitation for Privilege Escalation".
The technical exploitation of this vulnerability occurs through a carefully crafted POST request that targets the setvarsResults.cgi endpoint on the printer's web server. When this endpoint receives the malicious request, it processes the username and password change without proper authentication verification, effectively allowing unauthorized modification of administrative credentials. The prerequisite condition for exploitation is the disablement of the printer's protected mode, which serves as a security mitigation control that would normally prevent such configuration changes. This design flaw demonstrates a failure in implementing proper access controls and authentication checks, as the system should validate the identity of the requestor before accepting configuration modifications. The vulnerability essentially creates a backdoor path for privilege escalation that bypasses the normal authentication mechanisms. According to industry standards and security best practices, this represents a serious weakness in the printer's security architecture and violates fundamental principles of secure coding and access control design. The vulnerability impacts the confidentiality, integrity, and availability of the printer's management interface, potentially allowing attackers to gain full administrative control over the device.
The operational impact of this vulnerability extends beyond simple credential compromise and represents a significant risk to network security infrastructure. Once exploited, an attacker gains administrative access to the printer's web interface, which can be leveraged for various malicious activities including but not limited to printer configuration modification, data interception, or as a pivot point for further attacks within the network. The compromised printer could become a persistent threat vector, allowing attackers to maintain access while potentially using the device to monitor network traffic or disrupt printing operations. The vulnerability also impacts the organization's overall security posture by creating an unauthorized entry point that could be used for reconnaissance or as part of a broader attack campaign. From a compliance perspective, this vulnerability could result in violations of security standards such as ISO 27001, NIST Cybersecurity Framework, and various industry-specific regulations that require proper access controls and authentication mechanisms. The low attack complexity and high impact make this vulnerability particularly dangerous in environments where network segmentation is not properly implemented, as it could allow attackers to move laterally through the network undetected.
Mitigation strategies for CVE-2023-4957 should focus on both immediate remediation and long-term security improvements. The most immediate action is to enable the printer's protected mode configuration, which serves as the primary defense against this specific vulnerability. Organizations should also implement network segmentation to isolate these devices from critical network segments, ensuring that even if exploitation occurs, the attacker's access remains limited. Network monitoring should be enhanced to detect unusual traffic patterns targeting the setvarsResults.cgi endpoint, and access controls should be implemented to restrict which IP addresses can communicate with the printer's web interface. Regular firmware updates should be applied as soon as patches become available from Zebra Technologies, and the printer should be configured to use strong, unique administrative credentials that are changed periodically. Additional defensive measures include implementing network access control lists to restrict access to the printer's web management interface and establishing a regular audit process to verify that protected mode remains enabled. The vulnerability also highlights the importance of conducting regular security assessments of networked devices, particularly those that are often overlooked in traditional security monitoring programs. Organizations should consider implementing device identification and inventory management processes to ensure all networked printers are accounted for and properly secured. This vulnerability underscores the critical need for security by design principles in IoT and embedded devices, where the assumption of trust should never be made without proper authentication and authorization checks.