CVE-2024-34162 is a vulnerability identified in multiple Sharp Corporation multifunction printers (MFPs) involving the handling of LDAP authentication credentials. The affected devices' web interfaces are designed to conceal LDAP credentials even from administrative users; however, when LDAP authentication is configured to use the SIMPLE method, the device communicates with the LDAP server without encryption, transmitting credentials in clear-text. This exposure allows an attacker with network access to intercept and retrieve the LDAP password by capturing the network traffic between the MFP and the LDAP server. The vulnerability does not require any prior authentication or user interaction, making it accessible to remote attackers who can observe the network segment. The CVSS 3.1 base score is 5.3 (medium severity), reflecting the network attack vector, low complexity, no privileges required, no user interaction, and limited impact confined to confidentiality loss of LDAP credentials. The integrity and availability of the device or network are not directly affected. The affected product versions are detailed by Sharp Corporation but generally include multiple MFP models. No public exploits have been reported yet. This vulnerability primarily threatens the confidentiality of LDAP credentials, which could be leveraged to gain unauthorized access to directory services, potentially leading to further network compromise or data exposure. The root cause is the use of unencrypted LDAP SIMPLE authentication, which is a known insecure practice. Properly configured encrypted LDAP methods such as LDAPS or StartTLS would mitigate this risk.

For European organizations, this vulnerability poses a risk of credential disclosure that could lead to unauthorized access to corporate directory services, such as Microsoft Active Directory or other LDAP-based authentication systems. Since multifunction printers are often deployed in office environments and connected to internal networks, an attacker who gains network access—either physically or via compromised network segments—could intercept LDAP credentials transmitted in clear-text. This could facilitate lateral movement, privilege escalation, or data exfiltration within the organization. The impact is particularly significant for organizations with strict data protection requirements under GDPR, as unauthorized access to directory services may lead to exposure of personal data or disruption of authentication services. Additionally, sectors with high security needs such as government, finance, healthcare, and critical infrastructure in Europe could face increased risk if their Sharp MFPs are affected and improperly configured. However, since the vulnerability does not directly affect device integrity or availability, the immediate operational impact is limited to confidentiality breaches. The absence of known exploits reduces immediate risk but does not eliminate the potential for future attacks.

1. Immediately review and change LDAP authentication settings on all Sharp MFPs to avoid using SIMPLE authentication. 2. Configure LDAP communication to use encrypted protocols such as LDAPS (LDAP over SSL/TLS) or StartTLS to ensure credentials are never transmitted in clear-text. 3. Apply any firmware updates or patches provided by Sharp Corporation as soon as they become available, referencing official vendor advisories. 4. Segment network access to MFP devices, restricting communication to trusted management and directory servers only. 5. Monitor network traffic for signs of clear-text LDAP credential transmission and anomalous access patterns to LDAP servers. 6. Conduct regular security audits of MFP configurations and network architecture to ensure compliance with secure authentication practices. 7. Educate IT staff and administrators about the risks of unencrypted LDAP and enforce policies that prohibit SIMPLE authentication in production environments. 8. Consider deploying network intrusion detection systems (NIDS) capable of detecting LDAP credential leakage or suspicious LDAP traffic. 9. If possible, replace or upgrade legacy devices that do not support secure LDAP protocols. 10. Maintain an inventory of all Sharp MFPs and their firmware versions to prioritize remediation efforts.