CVE-2025-2146 is a critical buffer overflow vulnerability (CWE-787) found in the WebService Authentication processing component of multiple Canon multifunction and laser printers, including the Satera MF656Cdw and various Color imageCLASS and i-SENSYS models. This vulnerability affects firmware versions 05.07 and earlier. The flaw allows an unauthenticated attacker with network access to the affected device to trigger an out-of-bounds write condition. Exploitation can lead to the printer becoming unresponsive (denial of service) or, more severely, enable arbitrary code execution on the device. The vulnerability is remotely exploitable without requiring user interaction or privileges, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The impact spans confidentiality, integrity, and availability, as attackers could potentially execute malicious code to intercept print jobs, manipulate device settings, or disrupt printing services. The vulnerability is present in a broad range of Canon printers sold in Japan, the US, and Europe, with the European affected models including i-SENSYS and imageCLASS series. No public exploits are currently known in the wild, but the high CVSS score of 9.8 underscores the criticality and ease of exploitation. The lack of available patches at the time of publication increases the urgency for mitigation. This vulnerability highlights the risks associated with network-exposed printer management interfaces and the importance of timely firmware updates and network segmentation for such devices.

For European organizations, this vulnerability poses a significant risk due to the widespread deployment of affected Canon printer models in office environments. Successful exploitation could lead to complete compromise of the printer, enabling attackers to disrupt printing operations (impacting availability), intercept or alter sensitive printed documents (impacting confidentiality and integrity), and potentially use the compromised printer as a foothold for lateral movement within corporate networks. Given that these printers are often connected to internal networks and sometimes exposed to less secure network segments, the risk of exploitation is heightened. Critical business functions relying on printing, such as document handling, invoicing, and confidential communications, could be severely impacted. Additionally, the ability to execute arbitrary code could allow attackers to implant persistent malware or pivot to other critical systems, amplifying the threat to organizational cybersecurity posture.

1. Immediate network segmentation: Isolate affected printers on dedicated VLANs or network segments with strict access controls to limit exposure to untrusted networks and reduce attack surface. 2. Access control: Restrict network access to printer management interfaces to authorized personnel and trusted IP ranges only, using firewalls or access control lists. 3. Disable unnecessary services: If possible, disable WebService Authentication or related network services on the printers until patches are available. 4. Monitor network traffic: Implement network monitoring and intrusion detection systems to detect anomalous activity targeting printer devices. 5. Firmware updates: Closely monitor Canon’s advisories for patches addressing CVE-2025-2146 and apply updates promptly once released. 6. Incident response readiness: Prepare to isolate or remove affected devices quickly if exploitation is suspected to prevent lateral movement. 7. Vendor engagement: Engage with Canon support channels to obtain any available interim mitigations or beta patches. 8. Inventory and asset management: Maintain an accurate inventory of all affected printer models and firmware versions deployed within the organization to prioritize remediation efforts.