CVE-2004-2166 in Imagerunner 5000i
Summary
by MITRE
The print-from-email feature in the Canon ImageRUNNER (iR) 5000i and C3200 digital printer, when not using IP address range filtering, allows remote attackers to print arbitrary text without authentication via a text/plain email to TCP port 25.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/25/2019
The vulnerability identified as CVE-2004-2166 represents a critical security flaw in Canon ImageRUNNER digital printers, specifically the iR 5000i and C3200 models. This issue stems from improper authentication mechanisms within the printer's email processing functionality, creating an attack vector that allows unauthorized users to execute arbitrary printing commands remotely. The vulnerability is particularly concerning as it operates through the standard Simple Mail Transfer Protocol on TCP port 25, which is commonly accessible and often exposed to external networks without proper network segmentation.
The technical flaw manifests in the printer's handling of incoming email messages through its print-from-email feature. When configured without IP address range filtering, the printer fails to authenticate incoming email submissions, allowing any remote attacker to send text/plain email messages that are automatically processed and printed without requiring any form of user verification or authorization. This represents a fundamental breakdown in the printer's security model, as it essentially provides a backdoor for arbitrary content delivery through the email protocol. The vulnerability is classified under CWE-287, which deals with improper authentication mechanisms, and aligns with ATT&CK technique T1078.004 for valid accounts and T1566 for spearphishing via email, as it exploits email processing capabilities to gain unauthorized access to printing functions.
The operational impact of this vulnerability extends beyond simple unauthorized printing, as it creates potential for information disclosure, denial of service, and even social engineering attacks. Attackers could potentially send malicious content, including phishing emails, spam, or sensitive documents, to the printer's email interface, which would then be printed without any user consent. This could result in unauthorized document disclosure, particularly if the printer is located in a public or shared area. The vulnerability also enables resource exhaustion attacks where attackers could flood the printer with large volumes of email messages, potentially causing system instability or complete service disruption. Additionally, the flaw could be exploited as part of broader network reconnaissance efforts, as it provides an easily discoverable entry point for attackers to test printer configurations and gather information about network infrastructure.
Mitigation strategies for CVE-2004-2166 should focus on implementing proper network segmentation and access controls to prevent unauthorized access to the printer's email processing capabilities. Organizations should immediately configure IP address range filtering to restrict email access to trusted sources only, effectively blocking external attackers from submitting print jobs. Network administrators should also consider implementing email filtering solutions at the network level to prevent unauthorized email traffic from reaching the printer, and should disable the print-from-email feature entirely if it is not required for business operations. Additional protective measures include configuring firewalls to block inbound traffic on TCP port 25 to printer devices, implementing strong authentication for any remaining email processing functionality, and regularly auditing printer configurations to ensure that security controls remain effective. The vulnerability also highlights the importance of applying security patches and firmware updates to networked devices, as Canon likely released fixes for this specific issue in subsequent software updates. Organizations should establish regular security assessment procedures to identify and remediate similar vulnerabilities in other networked printing devices and should consider implementing centralized print management solutions that provide better access controls and monitoring capabilities.