CVE-2021-44734 in Lexmark
Summary
by MITRE • 01/20/2022
Embedded web server input sanitization vulnerability in Lexmark devices through 2021-12-07, which can which can lead to remote code execution on the device.
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Analysis
by VulDB Data Team • 01/26/2022
The vulnerability identified as CVE-2021-44734 represents a critical input sanitization flaw within the embedded web server component of Lexmark printing devices. This security weakness affects various Lexmark models released through December 7, 2021, creating a pathway for remote attackers to execute arbitrary code on the affected devices. The flaw stems from inadequate validation of user-supplied input data within the web interface, which serves as the primary management and configuration portal for these networked printing solutions. The vulnerability's impact extends beyond simple data manipulation as it enables full remote code execution capabilities, potentially allowing attackers to gain complete control over the affected devices.
The technical nature of this vulnerability aligns with CWE-20, which describes improper input validation, and falls under the broader category of web application security flaws. The embedded web server component processes HTTP requests from remote clients without sufficient sanitization of input parameters, creating opportunities for malicious actors to inject harmful commands or code sequences. This weakness exists in the device's web interface implementation where user inputs are not properly filtered or escaped before being processed by the underlying system. Attackers can exploit this by crafting specially formatted requests that bypass normal input validation mechanisms, ultimately leading to code execution within the device's operating environment.
From an operational perspective, the implications of CVE-2021-44734 are severe for organizations relying on Lexmark printing infrastructure. The remote code execution capability allows attackers to perform a wide range of malicious activities including data exfiltration, deployment of persistent backdoors, modification of print jobs, and potential lateral movement within network environments. The vulnerability affects devices that are typically connected to corporate networks, making them potential entry points for broader attacks. Given that many printing devices operate with elevated privileges and often have direct access to sensitive network resources, the compromise of these systems can lead to significant data breaches and operational disruptions. The vulnerability's presence in devices through December 2021 means that organizations with older Lexmark models remain at risk, particularly those with legacy device management systems.
Organizations should implement immediate mitigation strategies including firmware updates from Lexmark to address the input sanitization issues, network segmentation to isolate affected devices, and enhanced monitoring of network traffic for suspicious activities. The ATT&CK framework categorizes this vulnerability under T1059.007 for command and script interpreter execution, while the broader attack surface implications align with T1071.004 for application layer protocol usage. Security teams should also consider implementing web application firewalls to filter malicious requests and establish network access controls to limit remote administrative access to these devices. Regular vulnerability assessments and device inventory management become critical to identifying and remediating similar weaknesses across the organization's printing infrastructure.