Source: cve@mitre.org
LOGIN.EXE program in Novell Netware 4.0 and 4.01 temporarily writes user name and password information to disk, which could allow local users to gain privileges.
Local privilege escalation is possible on vulnerable Novell NetWare systems due to the insecure storage of user credentials by the LOGIN.EXE program. This flaw allows attackers with local access to retrieve usernames and passwords, enabling them to compromise user accounts and potentially gain unauthorized access to sensitive network resources.
Step 1: Local Access: The attacker must first gain local access to the vulnerable NetWare server. This could be achieved through physical access, compromised user accounts, or other local vulnerabilities.
Step 2: Identify Vulnerable System: The attacker identifies a NetWare 4.0 or 4.01 server.
Step 3: Trigger Login: The attacker attempts to log in to the NetWare server using a valid or invalid username and password. This action triggers the vulnerable LOGIN.EXE program.
Step 4: Credential Capture: The LOGIN.EXE program writes the username and password to a temporary file on the disk.
Step 5: File Access: The attacker accesses the temporary file containing the username and password. This can be done using standard file access tools.
Step 6: Credential Use: The attacker uses the captured username and password to log in to the system with the compromised user's privileges.
The vulnerability stems from a design flaw in the LOGIN.EXE program within Novell NetWare 4.0 and 4.01. The program temporarily writes the user's username and password to disk during the authentication process. This insecure storage mechanism, likely implemented for performance or debugging purposes, exposes sensitive credentials to local attackers. The root cause is the lack of secure handling of authentication data, specifically the failure to encrypt or securely erase the credentials after use. This allows attackers to directly read the credentials from the disk, bypassing the intended security mechanisms.
While no specific APTs are known to actively target this vulnerability due to its age and the prevalence of newer systems, any attacker with local access could exploit it. This vulnerability is not listed in the CISA KEV catalog due to its age and the limited number of systems still running these versions.
Monitor file system activity for the creation of temporary files in locations where LOGIN.EXE might write credentials. Specific filenames or patterns should be investigated.
Analyze system logs for failed login attempts, which could indicate an attacker attempting to gain access and subsequently exploiting the vulnerability.
Implement file integrity monitoring to detect unauthorized modifications to system files, including those related to user authentication.
Review system audit logs for suspicious activity, such as unauthorized access to user accounts or sensitive data.
Upgrade to a supported version of Novell NetWare. This is the most effective remediation.
Implement strong password policies, including password complexity and regular password changes.
Restrict physical access to the server. This is critical as the vulnerability requires local access.
Monitor system logs for suspicious activity and unauthorized access attempts.
Implement file system security measures to restrict access to sensitive files and directories.
If upgrading is not immediately possible, consider isolating the vulnerable server from the rest of the network to limit the impact of a potential compromise.