Source: cve@mitre.org
smcboot in Sun SMC (Sun Management Center) 2.0 in Solaris 8 allows local users to delete arbitrary files via a symlink attack on /tmp/smc$SMC_PORT.
Sun Management Center (SMC) 2.0 on Solaris 8 is vulnerable to a symlink attack, allowing local users to delete arbitrary files. This vulnerability, stemming from insecure file handling in the smcboot process, could lead to system instability, denial of service, or data loss.
Step 1: Target Selection: Identify a target file for deletion. This could be a critical system file like /etc/shadow, /etc/passwd, or a configuration file.
Step 2: Symlink Creation: The attacker creates a symbolic link in the /tmp directory (or another suitable location) named /tmp/smc$SMC_PORT pointing to the target file.
Step 3: Race Condition: The attacker attempts to trigger the smcboot process to create or interact with the /tmp/smc$SMC_PORT file. This is achieved by interacting with SMC in a way that causes smcboot to be invoked.
Step 4: File Deletion: If the race condition is won, smcboot will attempt to create or write to the symlink. This action, due to the symlink, will result in the deletion of the target file.
Step 5: Impact: The deletion of the target file can lead to system instability, denial of service, or privilege escalation depending on the file deleted.
The vulnerability lies within the smcboot process's handling of temporary files. Specifically, it creates a temporary file named /tmp/smc$SMC_PORT without proper security checks. A local attacker can exploit a race condition by creating a symbolic link pointing to a critical system file (e.g., /etc/shadow) before smcboot attempts to create or write to the temporary file. When smcboot then interacts with the temporary file, it inadvertently deletes the file the symlink points to, leading to arbitrary file deletion. The lack of input validation and secure file handling practices within the smcboot process is the root cause.
While no specific APT groups are directly linked to this CVE, the vulnerability's potential for arbitrary file deletion makes it attractive for any attacker seeking to disrupt or compromise a system. The age of the vulnerability means it could be incorporated into automated exploitation frameworks. Not listed on CISA KEV.
Monitor file system activity for unexpected deletions of critical system files, especially those in /etc or /var directories.
Analyze system logs for entries related to smcboot and file operations, particularly those involving /tmp/smc* files.
Implement file integrity monitoring (FIM) tools to detect changes to critical system files.
Network monitoring for unusual traffic patterns associated with SMC if it's network-accessible.
Upgrade to a patched version of Sun Management Center (if available).
Restrict access to the smcboot process to only authorized users.
Implement file system hardening by setting appropriate permissions on critical files and directories.
Regularly audit system logs for suspicious activity.
Consider disabling SMC if it is not essential for system operation.
Implement a security patch if one is available from Sun/Oracle.