CVE-2024-36251 is a vulnerability identified in the web interface of multiple Sharp Corporation multifunction printers. The issue stems from an out-of-bounds read triggered by improperly processed crafted HTTP requests, specifically involving a parameter in the billcodedef_sub_sel.html page. When an attacker sends a specially crafted HTTP request to this endpoint, the device attempts to read memory outside the intended bounds, resulting in a crash of the device’s web interface or the entire printer system. This vulnerability does not require any authentication or user interaction, making it remotely exploitable by any attacker with network access to the device. The impact is a denial-of-service (DoS) condition, as the affected printer becomes unresponsive or crashes, disrupting printing and scanning services. The CVSS v3.1 base score is 7.5, reflecting a high severity due to the ease of exploitation (network vector, no privileges required) and the complete loss of availability. No confidentiality or integrity impact is noted. The affected versions and specific models are detailed by Sharp Corporation, and organizations should consult vendor advisories for precise identification. Currently, there are no known exploits in the wild, but the vulnerability’s characteristics make it a candidate for potential exploitation in the future. The root cause is a lack of proper input validation and bounds checking in the web interface code handling HTTP parameters. This vulnerability highlights the risks associated with embedded web interfaces in networked devices, especially multifunction printers that are often connected to corporate networks.

For European organizations, the primary impact of CVE-2024-36251 is operational disruption due to denial-of-service conditions on affected Sharp multifunction printers. These devices are commonly used in offices, government agencies, and critical infrastructure sectors, where continuous availability is essential. A successful exploit could halt printing and scanning workflows, potentially delaying document processing and administrative tasks. While the vulnerability does not expose sensitive data or allow unauthorized control, the loss of availability can indirectly affect business continuity and productivity. In environments with high printer dependency or where printers are integrated into document management systems, the impact could be more pronounced. Additionally, repeated crashes could necessitate physical intervention or device replacement, increasing operational costs. The lack of authentication requirement means attackers could exploit this vulnerability from within the corporate network or potentially from external networks if the device’s management interface is exposed. This elevates the risk in organizations with insufficient network segmentation or weak perimeter defenses. Given the high CVSS score and ease of exploitation, European entities should prioritize mitigation to avoid service interruptions.

1. Apply official patches or firmware updates from Sharp Corporation as soon as they are released to address CVE-2024-36251. 2. Restrict network access to the web management interface of Sharp MFPs by implementing network segmentation and firewall rules that limit access to trusted administrators only. 3. Disable or restrict remote management features if not required, reducing the attack surface. 4. Monitor network traffic for unusual or malformed HTTP requests targeting billcodedef_sub_sel.html or other printer web interface endpoints, using intrusion detection/prevention systems (IDS/IPS). 5. Implement strict input validation and anomaly detection on network devices to detect potential exploitation attempts. 6. Conduct regular security audits of multifunction printers and related infrastructure to ensure configurations follow best practices. 7. Educate IT staff about this vulnerability and ensure incident response plans include steps for printer-related denial-of-service events. 8. Consider isolating multifunction printers on dedicated VLANs with limited access to critical network segments to contain potential impacts. 9. Maintain an inventory of all Sharp MFP devices to quickly identify and remediate affected units. These steps go beyond generic advice by focusing on network-level controls, monitoring, and operational readiness specific to multifunction printer environments.