CVE-2025-3079 is a vulnerability identified in Canon Inc.'s imageRUNNER Series multifunction and laser printers. The issue is classified under CWE-522, which pertains to insufficiently protected credentials. This vulnerability is described as a "passback" vulnerability, indicating that sensitive credential information used by the device is inadequately protected, potentially allowing unauthorized access or interception. The vulnerability affects all versions of the imageRUNNER Series, suggesting a systemic design or implementation flaw rather than a version-specific bug. According to the CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N), the attack vector is network-based (AV:N), with low attack complexity (AC:L), no attack or user interaction required (AT:N, UI:N), but requires high privileges (PR:H) to exploit. The vulnerability does not impact confidentiality, integrity, or availability directly (VC:N, VI:N, VA:N), but it has a high scope impact (SC:H) and high impact on security requirements (SI:H). This suggests that exploitation could lead to a significant security context change or privilege escalation within the device or network environment. No known exploits are currently reported in the wild, and no patches have been released yet. The vulnerability's nature implies that credentials stored or transmitted by the printer may be exposed or reused insecurely, which could allow an attacker with high privileges on the network or device to gain unauthorized access or move laterally within an organization’s infrastructure. Given the widespread use of Canon imageRUNNER devices in office environments, this vulnerability poses a risk to the confidentiality and security of sensitive documents and network access credentials.

For European organizations, this vulnerability could have significant implications. Canon imageRUNNER devices are commonly deployed in corporate, governmental, and educational institutions across Europe, often integrated into critical document workflows and network environments. Insufficient protection of credentials could lead to unauthorized access to the printer's administrative functions or network resources, potentially enabling attackers to intercept sensitive print jobs, manipulate device configurations, or pivot to other network systems. This could result in data breaches involving confidential documents, disruption of office operations, and compromise of internal networks. The impact is heightened in sectors with stringent data protection requirements such as finance, healthcare, and public administration, where exposure of sensitive information could lead to regulatory penalties under GDPR and damage to organizational reputation. The requirement for high privileges to exploit the vulnerability somewhat limits the attack surface to insiders or attackers who have already gained elevated access, but the lack of user interaction and low attack complexity means that once high privileges are obtained, exploitation is straightforward. The high scope impact indicates that the vulnerability could affect multiple components or systems beyond the printer itself, increasing the potential damage within interconnected enterprise environments.

To mitigate this vulnerability, European organizations should implement the following specific measures: 1) Restrict administrative access to Canon imageRUNNER devices strictly to trusted personnel and secure management networks using network segmentation and access control lists (ACLs). 2) Monitor and audit access logs on printers to detect unusual or unauthorized administrative activities promptly. 3) Employ strong authentication mechanisms for device management interfaces, including multi-factor authentication where supported, to reduce the risk of privilege escalation. 4) Isolate printers on dedicated VLANs or subnets to limit lateral movement opportunities for attackers who gain access. 5) Regularly review and update device firmware and software, and subscribe to Canon security advisories to apply patches immediately upon release. 6) Conduct internal security assessments and penetration tests focusing on printer security to identify and remediate configuration weaknesses. 7) Educate IT staff about the risks associated with printer vulnerabilities and the importance of securing these devices as part of the broader network security posture. These steps go beyond generic advice by focusing on network architecture, access controls, and proactive monitoring tailored to the specific risks posed by this vulnerability.