CVE-2024-29978 is a vulnerability identified in multiple Sharp Corporation multifunction printers (MFPs) where user passwords are handled insecurely. Specifically, the devices decrypt user passwords and store them in plaintext within device memory before any user logs in. This decrypted password data can be retrieved from coredump files generated by the device, which are typically used for debugging and crash analysis. Because these coredump files contain sensitive plaintext credentials, an attacker with access to these files could extract user passwords without needing to authenticate or interact with the device. The vulnerability has a CVSS 3.1 base score of 5.9, reflecting a medium severity level. The attack vector is network-based (AV:N), but the attack complexity is high (AC:H), meaning exploitation requires specific conditions or knowledge. No privileges or user interaction are required (PR:N/UI:N), and the impact is limited to confidentiality (C:H), with no impact on integrity or availability. The affected product versions are not explicitly listed but are referenced in vendor advisories. There are no known exploits in the wild at the time of publication. The vulnerability arises from insecure memory handling and insufficient protection of sensitive credential data in diagnostic files. This flaw could be exploited by attackers who gain access to device memory or coredump files, potentially through network intrusion or physical access to the device's storage. The exposure of plaintext passwords could facilitate further unauthorized access to the device or connected systems, undermining organizational security.

For European organizations, this vulnerability poses a significant confidentiality risk, especially in environments where Sharp MFPs are widely deployed for document processing and printing sensitive information. The exposure of plaintext passwords could enable attackers to compromise user accounts on the device, potentially leading to unauthorized access to scanned documents, print jobs, or administrative functions. This could result in data leakage of sensitive corporate or personal information. Although the vulnerability does not directly affect system integrity or availability, the compromise of credentials could be leveraged as a foothold for lateral movement within corporate networks. Sectors such as government, finance, healthcare, and legal services, which rely heavily on secure document handling, are particularly vulnerable. Additionally, the risk is heightened if coredump files are not adequately protected or if device management interfaces are exposed to untrusted networks. The medium CVSS score reflects that while exploitation is not trivial, the potential impact on confidentiality is high, warranting prompt attention. The lack of known exploits in the wild suggests that immediate widespread attacks are unlikely but does not preclude targeted attacks against high-value organizations.

1. Apply official patches and firmware updates from Sharp Corporation as soon as they become available to address this vulnerability. 2. Restrict access to device management interfaces and diagnostic data, including coredump files, ensuring only authorized personnel can retrieve or view them. 3. Implement network segmentation to isolate MFP devices from untrusted networks and limit exposure to potential attackers. 4. Regularly audit and monitor access logs on MFPs for unusual or unauthorized access attempts, especially related to diagnostic or memory dump retrieval. 5. Secure physical access to MFP devices to prevent unauthorized extraction of storage media containing coredump files. 6. Configure devices to minimize or disable automatic generation of coredump files where possible, or ensure these files are encrypted and securely stored. 7. Educate IT and security teams about the risks of plaintext password storage and the importance of handling diagnostic data securely. 8. Incorporate MFP security into broader endpoint and network security policies, including vulnerability management and incident response plans.