CVE-2025-55704 identifies a hidden functionality vulnerability in multiple Brother Industries multifunction printers (MFPs). This flaw allows an unauthenticated remote attacker to access the device's logs, which may contain sensitive information such as user activity, configuration details, or network data. The vulnerability is exploitable over the network without requiring privileges or user interaction, increasing its risk profile. The CVSS v3.1 base score of 5.3 reflects a low complexity attack vector with a confidentiality impact but no integrity or availability impact. The affected versions are not explicitly listed, requiring organizations to consult vendor advisories for precise identification. Although no public exploits have been reported, the exposure of logs can aid attackers in reconnaissance or lateral movement within a network. The vulnerability stems from undocumented or hidden features in the firmware or software of Brother MFPs that were not intended for external access. Given the widespread use of Brother MFPs in enterprise and public sector environments, this vulnerability could be leveraged to gather intelligence on internal operations or user behavior. The lack of authentication and user interaction requirements makes it easier for attackers to exploit remotely. However, the absence of integrity or availability impact limits the immediate operational damage. The vulnerability highlights the importance of securing device management interfaces and controlling access to diagnostic or logging functions.

For European organizations, the primary impact of CVE-2025-55704 is the potential unauthorized disclosure of sensitive information contained within MFP logs. This could include user credentials, network configuration details, document metadata, or usage patterns, which may facilitate further targeted attacks such as phishing, lateral movement, or privilege escalation. Sectors with strict data protection requirements, such as healthcare, finance, and government, are particularly vulnerable to compliance risks and reputational damage if sensitive data is exposed. The vulnerability does not directly affect device availability or integrity, so operational disruption is unlikely. However, the information leakage could undermine confidentiality and trust in document handling processes. Organizations with Brother MFPs exposed to untrusted networks or lacking proper network segmentation are at greater risk. The absence of known exploits reduces immediate threat but does not eliminate the risk of future attacks. Overall, the vulnerability represents a moderate threat to confidentiality that could be exploited to compromise broader network security postures in European enterprises.

Organizations should first identify all Brother MFP devices in their environment and verify affected firmware versions by consulting official vendor advisories. Until patches are available, restrict network access to these devices by implementing strict firewall rules and network segmentation, limiting communication to trusted management networks only. Disable any unnecessary or undocumented features and services on the MFPs that could expose logs or diagnostic data. Enable logging and monitoring on network devices to detect unusual access patterns to MFPs. Employ strong access controls and authentication mechanisms for device management interfaces where possible. Regularly update device firmware as soon as vendor patches addressing this vulnerability are released. Conduct security awareness training for IT staff to recognize potential exploitation attempts. Consider deploying network intrusion detection systems (NIDS) to alert on suspicious traffic targeting MFPs. Finally, review and sanitize logs stored on devices to minimize sensitive information exposure.