CVE-2001-0627 in OpenServer
Summary
by MITRE
vi as included with SCO OpenServer 5.0 - 5.0.6 allows a local attacker to overwrite arbitrary files via a symlink attack.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 12/15/2024
The vulnerability identified as CVE-2001-0627 represents a critical file system security flaw within the vi text editor distributed with SCO OpenServer versions 5.0 through 5.0.6. This issue stems from the improper handling of symbolic links during file operations, creating a privilege escalation vector that allows local attackers to manipulate file system contents in unintended ways. The vulnerability specifically affects systems running the SCO OpenServer operating system, which was widely used in enterprise environments during the early 2000s.
The technical root cause of this vulnerability lies in the vi editor's failure to properly validate file paths when processing symbolic links. When a user executes vi on a file that is actually a symbolic link pointing to another location, the editor does not adequately verify the target file's permissions or location before performing write operations. This behavior creates a race condition scenario where an attacker can manipulate the symbolic link target between the time vi checks the file permissions and when it actually writes to the file. The flaw operates under CWE-59: Improper Link Resolution, which classifies this as a path traversal vulnerability that can be exploited to gain unauthorized access to system resources.
From an operational impact perspective, this vulnerability presents significant security risks to systems running affected SCO OpenServer versions. A local attacker with basic user privileges can exploit this weakness to overwrite critical system files, configuration files, or even files owned by other users or system processes. The attack requires the attacker to have the ability to create symbolic links in the directory where the target file exists, which is typically feasible in many user contexts. This capability can lead to privilege escalation, system compromise, and potential data corruption or loss. The vulnerability is particularly dangerous because it operates at the file system level and can be exploited without requiring special privileges beyond local access.
The exploitation of this vulnerability aligns with several techniques documented in the MITRE ATT&CK framework, particularly focusing on privilege escalation and persistence mechanisms. Attackers can leverage this flaw to modify critical system binaries or configuration files, potentially creating backdoors or maintaining access to compromised systems. The attack pattern involves the creation of malicious symbolic links that redirect vi's write operations to target files of interest, demonstrating a classic symlink attack methodology. Organizations running SCO OpenServer systems should consider this vulnerability as part of their broader security posture assessment, particularly when evaluating legacy system security controls. The vulnerability also highlights the importance of proper file system permission handling and the need for robust input validation in system utilities, especially those with elevated privileges or system-level access capabilities. Remediation efforts should focus on applying vendor patches, implementing proper file system access controls, and conducting thorough security assessments of legacy systems to identify similar path traversal vulnerabilities.