Millions of Brother Printers at Risk from Unfixable Security Flaw

Your office printer might seem like a simple tool for printing documents, but it could be a weak link in your cybersecurity. A critical security flaw, known as CVE-2024-51978, affects millions of Brother printers, scanners, and label makers, allowing hackers to guess the default administrator password and take control of the device. This flaw, discovered in 2025, could let attackers access your network, steal sensitive information, or spread harmful software. Even worse, it can’t be fixed with a simple software update because it’s built into how the devices are made (Culafi, 2025; Kovacs, 2025). This article explains the risks, why traditional defenses aren’t enough, and how modern solutions like Cyber 2.0 can help keep your network safe.

The Hidden Danger in Your Printer

Printers, scanners, and label makers are common in offices, warehouses, and even homes, but when connected to a network or the internet, they become targets for hackers. The CVE-2024-51978 flaw lets attackers figure out the default admin password using the device’s serial number, giving them full control. From there, they can:

  • Steal Documents: Access files sent to the printer, like contracts or personal data.
  • Install Malware: Plant harmful software to attack other devices on your network.
  • Launch Broader Attacks: Use the printer as a gateway to target other systems.

This flaw affects 689 Brother models and some printers from FUJIFILM, Ricoh, Toshiba, and Konica Minolta, totaling 748 models across five brands (Rapid7, 2025). Other vulnerabilities found at the same time allow hackers to crash devices, steal sensitive information, or make unauthorized connections, making these devices even more dangerous (Kovacs, 2025).

Risk from Printers What it Means Why it's Dangerous
Default Password Access Hackers guess admin password Full control of the printer
Malware Installation Plants harmful software Spreads to other Devices
Network Gateway Entry point to your network Attacks critical systems
Why This Flaw Is Hard to Fix

Most security issues can be fixed with a software update, but CVE-2024-51978 is different. The default password is created during manufacturing based on the printer’s serial number, using a process that can’t be changed with a software patch. Fixing it requires Brother to alter how they make their devices, which could take years (Rapid7, 2025). In the meantime, these printers remain vulnerable, especially if left with default settings or connected to the internet.

Other issues found include:

  • Data Leaks: Hackers can retrieve sensitive information from the printer.
  • Device Crashes: Attackers can make the printer unusable.
  • Unauthorized Connections: Printers can be forced to connect to harmful networks or services.

These vulnerabilities highlight how even “simple” devices can pose big risks if not properly secured (Vijayan, 2024).

Why Traditional Defenses Fall Short

Traditional security tools, like antivirus programs and firewalls, rely on lists of known threats to spot problems. But new or “zero-day” attacks, like those exploiting CVE-2024-51978, can slip through because they’re not yet on those lists. Once a hacker gains access to a printer, they can move to other devices on the network, steal data, or install ransomware, often before traditional tools notice (Dark Reading, 2024). Past incidents with Canon and HP printers showed similar risks, where hackers used compromised printers to run unauthorized commands or steal data (Sharp, n.d.).

A Smarter Defense with Cyber 2.0

To combat these risks, businesses need tools that don’t just look for known threats but stop suspicious activity in its tracks. Cyber 2.0 is one such solution, designed to protect networks by:

  • Watching Behavior: It monitors how devices act and blocks anything unusual, like a printer trying to connect to a strange website.
  • Zero Trust: It assumes nothing is safe, requiring every device and user to prove their identity.
  • Network Scrambling: It uses a “Chaos Engine” to make network communication unreadable to hackers, preventing them from moving through your systems.
  • Full Monitoring: It provides a central dashboard with alerts, logs, and tracking to spot and investigate issues quickly.

Cyber 2.0 claims to block all types of cyberattacks, even new ones, by focusing on behavior rather than known threats. While promising, its effectiveness needs more real-world testing to confirm its claims (Cybersecurity Intelligence, n.d.).

Cyber 2.0 Feature How it Helps Why it's Different
Behavioral Monitoring Spots unusual activity Catches new threats
Zero Trust Verifies every device Stops unauthorized access
Network Scrambling Confuse hackers Prevents network movement
Central Dashboard Tracks and logs activity Quick response to issues
Real-World Example

Picture an office with a Brother printer vulnerable to this flaw. A hacker guesses the admin password and tries to use the printer to attack other devices. With Cyber 2.0, the system notices the printer acting strangely, blocks its actions, and alerts the IT team. The team can then trace the attack back to the printer and isolate it, preventing any damage. This kind of proactive defense is critical when hardware flaws can’t be patched quickly.

What You Can Do

To protect your network:

  1. Change Default Passwords: Set a strong, unique password for your printer if possible.
  2. Update Firmware: Check Brother’s support page for firmware updates that may reduce risks.
  3. Isolate Printers: Keep printers on a separate network from critical systems to limit damage.
  4. Use Advanced Security: Tools like Cyber 2.0 can monitor and block threats from devices like printers.
  5. Train Your Team: Teach employees to avoid connecting printers to unsecured networks.
Why This Matters in 2025

As more devices connect to the internet, from printers to smart thermostats, the risk of cyberattacks grows. In the Philippines, where web attacks are among the highest globally, businesses can’t afford to overlook devices like printers (Antivola, 2023). This flaw shows that even everyday office tools can be a gateway for hackers, making modern, proactive security essential.

The Path Forward

Traditional antivirus and firewalls aren’t enough to protect against unpatchable flaws like CVE-2024-51978. Solutions like Cyber 2.0 offer a smarter way to stay safe by focusing on behavior and Zero Trust principles. While no tool is perfect, combining these modern defenses with basic steps like changing passwords and updating firmware can keep your network secure.


Let’s Talk, If you want to explore how Bastion Inc. can help secure your organization with proactive, modern cybersecurity like Cyber 2.0—let’s connect.

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