Analysis of Printer Security Risks and Research on an Information Protection Framework

Excerpt   To need Printer security has long been a pressing concern; with the rapid advancement of IoT technologies and the continuous evolution and iteration of printer functionalities, Printers within enterprise and organizational networks are not only prime targets for data leakage but are increasingly becoming entry points and stepping stones for network compromise. By pursuing independent research and development from an information security perspective, we can achieve self-reliance and controllability, addressing the bottleneck challenges in core technologies. Establishing a printer platform security protection model based on trusted computing technology can enhance the security of print job transmission, storage, and other related processes, thereby strengthening the ability of office business systems to withstand cyberattacks.

Keywords ： Security, printer

The printer industry has a relatively small market size and high barriers to entry. To date, there are only about ten manufacturers worldwide that have fully mastered the independent research, development, and production of laser printers. The key barriers to entry in this sector stem from stringent proprietary intellectual‑property protections, high technical requirements, and a tightly controlled supply chain.

Printer components from different manufacturers lack a unified standard; each model requires custom‑designed parts. The R&D process must ensure compatibility with dozens of operating systems, hundreds of application software packages, support for over a hundred types of paper, and simulate thousands of usage scenarios—resulting in broad technical challenges, substantial investment, and extended development cycles.

As a critical component of office business systems, printers serve as the nexus between computer systems and information networks, functioning as central hubs for print-job data. Consequently, they are vulnerable to security threats and potential data breaches. Due to the unique characteristics of printer functionality and their operational contexts—such as highly customized and closed operating systems that preclude the installation of antivirus or access-control software, covert methods of data exfiltration, and insufficient user awareness of risks and inadequate preventive measures—existing information-security safeguards for printers remain limited, with correspondingly poor effectiveness.

To address the domestic software and hardware security requirements of printers—such as their built-in communication modules and main control units—we conduct security risk analyses on printer communication protocol stacks and embedded operating systems. We then develop a printer platform security protection model based on trusted computing technologies, which enhances the security of print job transmission and storage processes and strengthens the ability of office business systems to withstand cyberattacks. In recent years, cyberattack activities have grown increasingly sophisticated, evolving from primarily targeting computer terminals to expanding into non‑traditional targets such as industrial control systems and IoT devices. As an integral component of office business systems and an information output device, printers have been integrated into various networked information systems; moreover, printers themselves are equipped with embedded operating systems, storage devices, and… IP The protocol stack and other software and hardware components possess independent data-processing capabilities and can interact with the host. Network systems have given rise to cybersecurity threats that far exceed expectations, and their resilience against cyberattacks can impact the entire network infrastructure.

The secure operation of the system. The security risks associated with printers stem from modules or components within the print‑job system that comprises the printer and the host computer. For example, printer driver vulnerabilities pose a significant risk: printer drivers interact directly with the operating system, potentially gaining access to classified computers and even extracting information from systems on classified networks by illegally invoking OS interfaces, resulting in a very high risk level. Another example is printer interface security risks: the printer interface serves as an essential pathway for transmitting print data, yet its communication protocols often rely on plaintext transmission. formula Moreover No device management or identification capabilities.

1. Printers have become a weak link in network security.

1.1 Common Security Vulnerabilities in Printers

The printer system has weak resistance to cyberattacks and poor protection against viruses. Attackers can exploit… TCP/IP Connect the printer to the network; once connected, access its various network services, including FTP ， SMB ， SNMP ， LPD ， IPP ，9100 Ports, etc., are exploited by sending malicious documents to launch attacks. For example, targeting printers… Web Cross-site printing is an attack technique whereby, when a user visits a malicious website crafted by the attacker, the attacker sends to the user’s browser JavaScript Code, utilizing a hidden one Iframe To the user’s internal network printer’s 9100 The port sends the printer’s built-in FTP The server imposes no restrictions on commands. By exploiting this vulnerability, hackers can FTP Any connection to the server can easily cause abnormal operation and malfunctions in network printers. Furthermore, attackers can exploit network printers… IP , compromising other computer devices within the network segment and causing information leakage and other security incidents.

Security Design Flaw in Printer Cache Information 。 Printers, constrained by current network‑transmission conditions, exhibit a degree of network latency in practical use. This latency leads to the accumulation of cached data within network devices. Depending on the size of the printer’s cache memory, such cached information is repeatedly overwritten and deleted in an ongoing cycle. As a result, cached data may remain in the printer for a non‑trivial period; if this data is sensitive, it becomes vulnerable to theft during cyberattacks—particularly in centralized document‑printing systems, where large volumes of confidential materials are temporarily stored in the printer’s cache, posing significant security risks. Moreover, printers lack robust mechanisms for identity authentication and authorization. With the rapid advancement of intelligent networking technologies, printer control systems have also become increasingly sophisticated. To ensure the security of cached data and to regulate operations such as modifying, retrieving, or downloading cached information, it is essential to verify the identity of the operator. However, common user‑authentication methods—such as fingerprint scanning, username/password combinations, or print‑card verification—are typically implemented via third‑party devices, leaving the printer itself without its own built‑in authentication and authorization capabilities. This deficiency makes printers susceptible to information leakage in the event of cyberattacks. and other phenomena.

2. Security Risk Analysis of Printer Modules or Components

Conduct a security risk and vulnerability analysis of printer modules or components—including the main control unit, data transmission unit, external interfaces, drivers, and printing protocols—and undertake research on issues such as printer‑embedded firmware, printer port access control, print‑data transmission, print‑job authentication, and the handling of cached print‑related data.

2.1 Major Hardware Security Risks of Printers

The printer’s main control chip harbors certain security vulnerabilities, potentially enabling it to function as a covert spy. This allows hackers to monitor and steal the contents of printed documents, thereby infringing on users’ privacy and exposing businesses to financial losses and reputational damage. Furthermore, information stored within the printer may be leaked to unauthorized parties, resulting in the compromise of sensitive documents such as financial reports, payroll records, and contracts, which can inflict substantial harm on organizations. In addition, printers can serve as entry points for cyberattacks; they can be remotely controlled or exploited through vulnerabilities, compromising the security of corporate networks and other critical systems.

Many printer data breaches have occurred throughout history, such as… 2017 year 15 Ten thousand printers and 2018 Approximate age 5 The incident involving the compromise of tens of thousands of printers highlights the risks posed by printers as a weak link in information security.

Printers are input/output devices that enjoy a high degree of trust from office computers. They not only directly handle confidential print and copy jobs but can also collect users’ sensitive information through software installed on PCs, tablets, or smartphones. All printers come equipped with flash memory, and some high-end models—such as multifunction copiers—often include large-capacity hard drives, effectively turning them into network‑based storage servers capable of actively gathering user data. Due to the unique functions and usage scenarios of printers, they present more potential avenues for information leakage than computers or mobile phones, making them easier for attackers to exploit. Coupled with their customized, closed operating systems—precluding the installation of antivirus or security‑control software—and the covert nature of data‑exfiltration methods, combined with users’ limited awareness of risks and weak preventive measures, there are few effective information‑security safeguards for printers, and those that do exist tend to be inadequate. Consequently, techniques for implanting malicious code into printers or activating existing malware stored within them are numerous and difficult to detect and mitigate. Certain untrusted printers connected to our office networks are akin to dormant cancer cells lurking in our bodies: they can be activated at any time, posing threats such as network outages, file deletions, and system crashes. The primary channels through which attackers leverage printers to steal information or launch cyberattacks include the following:

  Utilize the Internet. Many printers offer internet connectivity via Ethernet cables or wireless modules such as Wi‑Fi, enabling shared printing and remote printing. After installation, some printers frequently exchange data with overseas servers over the internet. This pathway can be exploited to exfiltrate users’ sensitive information or to receive remote control commands and malicious code. Some printers lack built-in networking capabilities but can join your office network through a computer connected via USB, thereby facilitating shared printing. If devices on the office network are connected to the internet, even printers without native networking can leverage this gateway to communicate with external systems.

  Leveraging the internal network. Whether or not it has network capabilities, a printer can serve as a device connected to the office network. In addition to accessing documents that users have already printed, printers may also gain access to confidential files stored on users’ computers—files that have not yet been printed—and store them in their own memory. If vulnerabilities or pre‑configured backdoors in an untrusted printer are discovered and exploited by insiders (such as spies), the information they contain could be exfiltrated. Typically, computers trust printers, making them an easy foothold for malicious internal users to bridge between different systems, bypass network‑management controls, steal data from other machines, or launch targeted attacks.

  Leveraging consumables and accessories. Most printer consumables are equipped with chips, which typically serve functions such as device identification, print‑count tracking, estimation of remaining consumable life, and retrieval of print‑control parameters specific to that consumable. In addition to consumables, certain printer accessories may also incorporate similar chips or covertly have wireless chips installed in hidden locations. If a printer designer intends to engage in malicious data exfiltration, they might select chips with large storage capacities and, when necessary, program the printer to offload users’ sensitive information onto those chips. Malicious actors could likewise exploit chips embedded in new consumables or accessories to deliver malware, activation commands, or other payloads to the printer, thereby launching attacks against office systems.

  Take advantage of on-site maintenance opportunities. Prolonged wear can compromise component accuracy, and polymeric materials tend to degrade in performance over time. High‑volume, high‑end printers—especially copiers and production‑grade models—require regular maintenance akin to automotive servicing. Given the complex architecture of printers, which varies significantly from one model to another, and the near‑total lack of part interchangeability, repairing or replacing components is highly challenging. Consequently, such maintenance must be performed by external specialists who are thoroughly familiar with the specific model, posing substantial information‑security risks to users. Printers often include debugging interfaces, and may even harbor deliberately concealed communication ports. Test instruments like multimeters and oscilloscopes can be modified to enable communication with the printer, allowing attackers to extract and store data while also injecting malicious code or activating harmful functions. Even more concerning, service technicians might exploit specific key combinations on the printer’s control panel to activate hidden features pre‑installed within the device.

  By leveraging printer paper, users can add visible watermarks to printed documents when needed. There is also an alternative—less conspicuous watermarking techniques, such as steganography, which include subtle yellow dots, localized font adjustments, minute changes in text position or size, and modifications to image halftone algorithms and parameters. If sensitive information is embedded into our printed materials using such steganographic methods, it could pose a risk of data leakage. Furthermore, when we photocopy confidential documents, sensitive keywords within the files may be detected by the printer, enabling eavesdropping or triggering certain hidden malicious functions.

  Installing data‑exfiltration devices. Printers with inadequate security protections may have vulnerabilities that hackers can exploit remotely to carry out data theft or launch attacks. Once a printer with insufficient safeguards is disassembled, attackers can modify its firmware to enable data exfiltration and other malicious activities; they might even install a communication module inside the device to transmit user information via wireless signals or power‑line communication, or to send malicious programs or commands to activate harmful functions.

  As printer users—particularly those in organizations with stringent confidentiality requirements—information leaks can pose significant risks or losses. To make our day-to-day information security management more effective, we must not overlook the proper selection and management of printers. The espionage and attack techniques discussed earlier are all carried out through a printer’s hardware and software, often stemming from the manufacturer’s deliberate malice. Therefore, a printer’s trustworthiness, along with its built-in security enhancements and protective features, should be key considerations when choosing a product. As domestic manufacturers gain greater market presence, user awareness of information security risks continues to rise, and national regulations on the information security of printing devices become increasingly stringent, these latent information‑security threats will gradually recede from the office environment.

How to effectively manage the confidentiality of laser printers and eliminate potential risks of information leakage has become an essential part of our work. A laser printer is a printing device that combines laser scanning technology with electrophotographic technology. The operating process of a laser printer can be divided into information conversion, electrostatic image formation, transfer and output, and the laser printer’s… “Confidentiality minefield.”

Laser printers pose numerous risks of information leakage, including leaks from circuit boards, hard drives, toner cartridges, unauthorized photography, and wireless connections. To prevent malicious actors from using laser printers to conduct espionage and to effectively safeguard state secrets, it is essential to strengthen implementation across multiple dimensions, such as standardized procurement, technical inspections, routine management, repair and maintenance, and decommissioning and disposal.

• [1] Wang Ledong , Tu Hang , Hou Wenrui . Research on Printer Security Risk Analysis and an Information Protection Framework [J]. Cybersecurity Technologies and Applications , 2023, (06): 140-142.