CVE-2018-0680 in Denbun
Summary
by MITRE
Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) uses hard-coded credentials, which may allow remote attackers to read/send mail or change the configuration.
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Analysis
by VulDB Data Team • 04/13/2020
The vulnerability identified as CVE-2018-0680 affects Denbun by NEOJAPAN Inc. software products including Denbun POP version V3.3P R4.0 and earlier, and Denbun IMAP version V3.3I R4.0 and earlier. This security flaw represents a critical configuration weakness that exposes systems to unauthorized remote access. The vulnerability stems from the implementation of hard-coded credentials within the software components, which violates fundamental security principles and creates persistent access vectors for malicious actors.
The technical flaw manifests through the inclusion of hardcoded authentication credentials within the application code or configuration files. These credentials remain static and unchanged regardless of system updates or security policies, creating a persistent backdoor that attackers can exploit. The vulnerability falls under CWE-798, which specifically addresses the use of hard-coded credentials in software implementations. This weakness enables attackers to bypass normal authentication mechanisms and gain unauthorized access to email services. The hard-coded credentials typically include usernames and passwords that are embedded directly into the application source code, making them easily discoverable through reverse engineering or code analysis techniques.
The operational impact of this vulnerability is severe and multifaceted, affecting both the confidentiality and integrity of email communications. Remote attackers can leverage these hardcoded credentials to read sensitive email messages, send unauthorized emails from compromised accounts, and potentially modify system configurations. This creates a significant risk of data breaches, email spoofing, and unauthorized system manipulation. The vulnerability particularly affects organizations using these specific versions of Denbun software, where the hardcoded credentials could provide attackers with persistent access to email infrastructure. The implications extend beyond simple unauthorized access as attackers could use this foothold to establish further persistence within the network or conduct more sophisticated attacks.
Mitigation strategies for CVE-2018-0680 should prioritize immediate software updates and patches from the vendor, as this vulnerability affects specific versions of the Denbun software. Organizations should implement comprehensive credential management practices, including regular credential rotation and the elimination of hardcoded authentication values in software code. The remediation process should include thorough code reviews to identify and remove any hardcoded credentials from all application components. Additionally, network segmentation and monitoring should be implemented to detect unauthorized access attempts. This vulnerability aligns with ATT&CK technique T1078 which covers valid accounts and credential access, and represents a classic example of poor secure coding practices that violates security best practices established by frameworks such as the OWASP Top Ten. Organizations should also consider implementing privileged access management solutions and conducting regular security assessments to identify similar hardcoded credential issues within their software infrastructure.