CVE-2003-1056 in Solaris
Summary
by MITRE
The ed editor for Sun Solaris 2.6, 7, and 8 allows local users to create or overwrite arbitrary files via a symlink attack on temporary files.
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Analysis
by VulDB Data Team • 06/27/2019
The vulnerability identified as CVE-2003-1056 represents a critical security flaw in the ed text editor component of Sun Solaris operating systems versions 2.6, 7, and 8. This issue stems from improper handling of temporary files during the editor's operation, creating an exploitable condition that allows local attackers to manipulate the file system through symbolic link attacks. The vulnerability specifically targets the editor's temporary file creation mechanisms, which are inherently susceptible to race conditions and insecure file handling practices that have been documented in various security frameworks including CWE-377 and CWE-378.
The technical implementation of this vulnerability exploits the predictable naming patterns and lack of proper file permission checks when the ed editor creates temporary files. When the editor processes certain commands, it generates temporary files in world-writable directories such as /tmp without sufficient security controls to prevent malicious users from creating symbolic links with the same names. This insecure temporary file creation pattern creates a window of opportunity where an attacker can establish symbolic links before the editor creates its actual temporary files, thereby causing the editor to write data to attacker-controlled locations. The flaw aligns with ATT&CK technique T1548.001 for privilege escalation and T1059 for command execution through compromised system utilities.
The operational impact of this vulnerability extends beyond simple file manipulation as it provides attackers with the capability to overwrite critical system files, create malicious files with elevated privileges, or establish persistence mechanisms within the target system. Local users who can execute the ed editor can leverage this weakness to gain unauthorized access to sensitive system resources, potentially leading to complete system compromise. The vulnerability affects systems where the ed editor is installed and accessible to local users, making it particularly dangerous in multi-user environments where privilege separation is essential. Security researchers have classified this as a privilege escalation vector that can be exploited without requiring special privileges beyond local user access, making it a significant concern for system administrators managing Solaris environments.
Mitigation strategies for CVE-2003-1056 should focus on immediate system hardening measures including restricting write permissions to temporary directories, implementing proper file access controls, and ensuring that temporary files are created with secure naming conventions and appropriate permissions. System administrators should consider patching affected Solaris versions or applying vendor-specific security updates that address the insecure temporary file handling in the ed editor. Additionally, implementing mandatory access controls through SELinux or similar security frameworks can provide additional protection layers against such exploitation attempts. The vulnerability demonstrates the importance of secure coding practices and proper file handling mechanisms, particularly in system utilities that operate with elevated privileges or have access to sensitive system resources. Organizations should conduct comprehensive vulnerability assessments to identify other potentially affected system components and ensure that all temporary file operations follow security best practices as outlined in industry standards such as those provided by the Open Web Application Security Project and NIST guidelines for secure software development.