CVE-2013-4614 in MX340
Summary
by MITRE
English/pages_MacUS/wls_set_content.html on the Canon MG3100, MG5300, MG6100, MP495, MX340, MX870, MX890, MX920, and MX922 printers shows the Wi-Fi PSK passphrase in cleartext, which allows physically proximate attackers to obtain sensitive information by reading the screen of an unattended workstation.
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Analysis
by VulDB Data Team • 06/20/2024
This vulnerability exists in Canon multifunction printers including models MG3100, MG5300, MG6100, MP495, MX340, MX870, MX890, MX920, and MX922, where the wireless security passphrase is displayed in cleartext on the device's web interface. The flaw is particularly concerning because it exposes the Wi-Fi pre-shared key (PSK) through the web-based management interface accessible at English/pages_MacUS/wls_set_content.html, making it trivial for attackers to obtain sensitive network credentials. This vulnerability represents a classic case of insufficient output sanitization and insecure information disclosure, where the system fails to properly protect sensitive authentication data during display operations.
The technical implementation of this vulnerability stems from the printer's web interface design, which does not adequately mask or obfuscate the Wi-Fi PSK during configuration or display phases. When users access the wireless settings page, the system presents the passphrase in plain text format, allowing anyone with physical access to the device or network visibility to capture the credentials. This issue directly violates security best practices for credential handling and demonstrates poor separation of concerns in the user interface implementation. The vulnerability can be classified under CWE-200 as exposure of sensitive information and CWE-312 as cleartext storage of sensitive data, both of which are fundamental security weaknesses in information security systems.
The operational impact of this vulnerability is significant for organizations using these Canon printers, as it creates an attack surface that allows physical proximity attackers to obtain network credentials without requiring any advanced technical skills or network privileges. An attacker with physical access to an unattended workstation or the printer itself can simply read the displayed passphrase and use it to gain unauthorized access to the wireless network. This creates a substantial risk for corporate environments where printers are placed in common areas, conference rooms, or other locations where unauthorized individuals might gain physical access. The vulnerability can be exploited as part of a broader attack chain, potentially enabling lateral movement within the network or access to additional systems that share the same wireless network credentials. The attack vector aligns with the ATT&CK technique T1566 for credential access through physical access to devices.
Organizations should implement immediate mitigations including restricting physical access to these devices, implementing network segmentation to isolate printer networks, and disabling unnecessary web interfaces on the devices. Administrators should also consider implementing additional authentication controls and regularly auditing device configurations to ensure sensitive information is not exposed. The vulnerability highlights the importance of proper information security controls during the design and implementation phases of networked devices, emphasizing the need for comprehensive security testing and validation of user interfaces that handle sensitive data. Long-term solutions should include firmware updates from Canon that address the information disclosure issue, proper input validation, and output sanitization mechanisms to prevent cleartext exposure of sensitive credentials.