Printer Security Flaws Expose Critical Risks Across Brands

Security researchers have recently uncovered multiple vulnerabilities in a wide range of printer models from various manufacturers, including Brother, Fujifilm, Ricoh, and Toshiba. Rapid7, in collaboration with Brother and JPCERT Coordination Center, identified eight vulnerabilities across 689 Brother multifunction printers. The most critical flaw allows unauthorized access to admin passwords, posing a significant security risk.

These vulnerabilities extend beyond Brother printers, affecting devices from other brands as well. Fujifilm, Ricoh, Konica Minolta, and Toshiba models are also susceptible to some or all of these security flaws. The vulnerabilities range from leaking sensitive information and triggering buffer overflows to crashing devices and disclosing passwords of external services. These issues can potentially be exploited by malicious actors to compromise the integrity and confidentiality of printer systems.

Among the identified vulnerabilities, the most severe is an authentication bypass flaw that enables remote attackers to extract a device’s serial number and generate its default admin password. This issue is deeply rooted in Brother’s password generation process, making it challenging to mitigate through a simple firmware update. Brother plans to implement a new manufacturing process to eliminate this vulnerability in future printer models and has provided workarounds for existing devices.

Rapid7, as the CVE Numbering Authority, has meticulously documented each vulnerability and its impact on the affected printer models. Brother has issued advisories for laser and inkjet printers, document scanners, and label printers to inform users about the potential risks associated with these vulnerabilities. The collaboration between Rapid7, Brother, and JPCERT/CC has been instrumental in identifying, addressing, and verifying fixes for these critical security flaws.

The discovery of these vulnerabilities underscores the importance of ongoing security assessments and proactive measures to safeguard networked devices. As the digital landscape evolves, cyber threats continue to proliferate, necessitating robust security protocols and timely responses to potential risks. Organizations are urged to stay vigilant, apply security patches promptly, and implement best practices to mitigate the impact of security vulnerabilities on their infrastructure.

Stephen Fewer, the researcher behind the zero-day project that uncovered these vulnerabilities, initiated the disclosure process with Brother in May 2024. Subsequent collaboration with JPCERT/CC and Rapid7 led to the identification and resolution of these vulnerabilities over an 11-month period. The final disclosure was made in June 2025, emphasizing the importance of coordinated efforts in addressing cybersecurity challenges in complex technology ecosystems.

In conclusion, the vulnerabilities discovered in Brother and other printer models serve as a stark reminder of the evolving threat landscape in the digital realm. By fostering collaboration among security researchers, manufacturers, and cybersecurity experts, it is possible to enhance the resilience of networked devices and mitigate potential risks effectively. The proactive identification and remediation of security vulnerabilities are essential steps in fortifying the cybersecurity posture of organizations and protecting sensitive data from malicious exploitation.