Canon Inc. has recently disclosed significant security vulnerabilities affecting a broad spectrum of their printer models, including production printers, office multifunction devices, and laser printers. These vulnerabilities, identified as CVE-2025-3078 and CVE-2025-3079, pose substantial risks by potentially allowing unauthorized access to sensitive authentication information, thereby compromising network security.
Overview of the Vulnerabilities
The vulnerabilities in question have been assigned a Common Vulnerability Scoring System (CVSS) v3.1 base score of 8.7, categorizing them as high-severity threats. CVE-2025-3078 primarily impacts production printers and office multifunction printers, while CVE-2025-3079 affects office and small office multifunction printers as well as laser printers. These flaws enable attackers with administrative privileges to redirect device authentication attempts to malicious servers under their control, leading to unauthorized access and potential data breaches.
Technical Details
The core issue lies in the insufficient protection of credentials (CWE-522). Canon devices transmit authentication information for external services without adequate safeguards, making them susceptible to interception. Exploitation of these vulnerabilities allows attackers to acquire SMTP (Simple Mail Transfer Protocol) and LDAP (Lightweight Directory Access Protocol) connection credentials configured within the affected devices.
In a typical attack scenario, an adversary with administrative access can modify the LDAP server IP address in the device configuration. This alteration redirects authentication requests to a rogue server controlled by the attacker, capturing credentials in plaintext. Such passback attacks exploit the trust relationships between multifunction peripherals (MFPs) and critical network services, facilitating unauthorized access and potential lateral movement within the network.
Potential Impact
The exploitation of these vulnerabilities can have severe consequences, including:
– Unauthorized Access: Attackers can gain access to sensitive information, including user credentials and confidential documents.
– Network Compromise: With acquired credentials, attackers can infiltrate other network systems, leading to widespread security breaches.
– Operational Disruption: Malicious actors can disrupt printing operations, causing significant downtime and productivity loss.
Mitigation Strategies
While Canon is actively developing firmware patches to address these vulnerabilities, the company has provided interim mitigation guidelines to enhance security:
1. Network Configuration: Avoid connecting devices directly to public internet networks. Instead, use private IP addresses within secure network environments protected by firewalls, routers, or Wi-Fi routers.
2. Access Control: Restrict administrative access to trusted personnel and implement robust authentication mechanisms to prevent unauthorized configuration changes.
3. Regular Updates: Monitor Canon’s official channels for firmware updates and apply them promptly to ensure devices are protected against known vulnerabilities.
4. Network Monitoring: Implement continuous monitoring of network traffic to detect and respond to suspicious activities promptly.
Broader Context
This disclosure is part of a series of security advisories issued by Canon in recent years. In February 2024, Canon addressed multiple buffer overflow vulnerabilities (CVE-2023-6229 through CVE-2023-6234 and CVE-2024-0244) in small office multifunction printers and laser printers. These flaws could allow unauthenticated remote attackers to execute arbitrary code or launch Denial-of-Service (DoS) attacks if the devices were connected directly to the internet without proper network protections.
Additionally, in May 2023, Canon identified vulnerabilities in the IJ Network Tool (CVE-2023-1763 and CVE-2023-1764) that could enable attackers on the same network to acquire sensitive information related to Wi-Fi connection setups. The company recommended using printers within trusted network connections and provided guidance on securing products when connecting to a network.
In July 2023, Canon warned users that sensitive Wi-Fi connection settings stored in the memories of various inkjet printers might not be deleted during the standard initialization process. This oversight could expose users’ network information when the devices are repaired, sold, or disposed of. Canon provided specific instructions to ensure the complete removal of Wi-Fi settings before transferring ownership of the devices.
Conclusion
The recent vulnerabilities underscore the critical importance of robust security practices in managing networked devices. Organizations and individuals using Canon printers should implement the recommended mitigation strategies and stay vigilant for firmware updates to protect their networks from potential attacks. Regularly reviewing device configurations, restricting administrative access, and ensuring secure network environments are essential steps in safeguarding against these and future vulnerabilities.
