CVE-2006-4537 in OpenVMS
Summary
by MITRE
NET$SESSION_CONTROL.EXE in DECnet-Plus in OpenVMS ALPHA 7.3-2 and Alpha 8.2 writes a password to an audit log file when there is a successful connection after a "network breakin" event, which allows local users to obtain passwords by reading the file.
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Analysis
by VulDB Data Team • 08/03/2018
The vulnerability described in CVE-2006-4537 represents a critical security flaw in the DECnet-Plus implementation within OpenVMS operating systems, specifically affecting versions Alpha 7.3-2 and Alpha 8.2. This issue stems from improper handling of authentication events within the network security framework, creating a significant information disclosure risk that directly violates fundamental security principles. The flaw manifests when the system processes successful connections following a network breakin event, where the password associated with the successful authentication is inadvertently written to an audit log file without proper sanitization or access controls. This behavior creates a direct pathway for privilege escalation and credential theft that aligns with CWE-200 (Information Exposure) and CWE-522 (Insufficiently Protected Credentials) classifications.
The technical implementation of this vulnerability involves the NET$SESSION_CONTROL.EXE component which manages session control operations within the DECnet-Plus network protocol stack. When a network breakin event occurs followed by a successful connection attempt, the system's session management logic fails to properly sanitize authentication data before writing it to the audit log file. This improper data handling creates a persistent exposure where local users with access to the audit log file can directly read and extract passwords from the log entries. The vulnerability specifically targets the audit logging mechanism rather than the authentication process itself, demonstrating a weakness in the principle of least privilege and proper data handling practices. The flaw represents a failure to implement proper access controls on sensitive audit data, which is a direct violation of security best practices and standards such as those outlined in the NIST SP 800-53 security controls.
From an operational impact perspective, this vulnerability creates a severe risk for OpenVMS systems running the affected DECnet-Plus versions, as it provides local attackers with immediate access to authentication credentials without requiring additional attack vectors. The implications extend beyond simple credential theft to potentially enable further system compromise through lateral movement and privilege escalation attacks. Security professionals should note that this vulnerability operates at the system level and affects the integrity of the authentication framework, making it particularly dangerous in environments where multiple users share system resources. The attack surface is limited to local users who can access the audit log file but does not require network access or specialized tools, making it an attractive target for insider threats or compromised local accounts. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under T1078 (Valid Accounts) and T1566 (Phishing for Information) where credential exposure through log files serves as a foundational attack vector.
The recommended mitigation strategies for this vulnerability involve immediate implementation of proper access controls on audit log files, ensuring that only authorized system administrators can access these sensitive records. System administrators should configure appropriate file permissions and access controls to prevent local users from reading the audit log files where passwords are stored. Additionally, the system configuration should be reviewed to disable or modify the password logging behavior in audit logs, or implement log sanitization mechanisms that remove sensitive information before writing to audit files. Organizations should also implement monitoring and alerting mechanisms to detect unauthorized access attempts to audit log files, which can help identify potential exploitation attempts. The remediation process should include comprehensive system auditing to identify all instances of the vulnerable DECnet-Plus implementation and ensure proper patching or configuration changes are applied across all affected systems. Regular security assessments should be conducted to verify that audit log files maintain appropriate access controls and that no sensitive information is inadvertently exposed through system logging mechanisms.