CVE-2004-1349 in Solaris
Summary
by MITRE
gzip before 1.3 in Solaris 8, when called with the -f or -force flags, will change the permissions of files that are hard linked to the target files, which allows local users to view or modify these files.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/22/2025
The vulnerability described in CVE-2004-1349 represents a significant security flaw in the gzip compression utility version 1.3 and earlier implementations found in Solaris 8 operating systems. This issue specifically manifests when gzip is executed with the -f or --force command line flags, creating a scenario where the utility's behavior extends beyond its intended functionality to include unintended file permission modifications. The vulnerability stems from how gzip handles hard links during the compression process, particularly when the force flag is invoked to overwrite existing files. When a hard-linked file is targeted for compression with force, the utility modifies the permissions of the original file, affecting all hard links pointing to that inode, thereby creating a potential security risk that extends beyond the immediate target file.
The technical implementation of this vulnerability involves the fundamental way Unix-like systems handle hard links and file permissions. In Unix filesystems, hard links are multiple directory entries that point to the same inode, sharing identical file metadata including permissions. When gzip with the force flag encounters a hard-linked file, it performs operations that inadvertently alter the permissions of the underlying inode, affecting all hard links associated with that file. This behavior violates the principle of least privilege and creates a scenario where unauthorized modifications to file permissions can occur. The flaw essentially allows a local user to manipulate the permission structure of files that they might not normally have access to modify, creating a vector for privilege escalation or data access manipulation. This issue is particularly concerning in multi-user environments where file access controls are critical for maintaining system security and data integrity.
The operational impact of CVE-2004-1349 extends beyond simple permission modification, creating potential pathways for data leakage and unauthorized access within systems. Local users who can execute gzip with force flags gain the ability to indirectly access files they might not otherwise be able to view or modify, as the permission changes affect all hard links to the affected files. This vulnerability can be exploited to bypass traditional file access controls, potentially allowing attackers to read sensitive information or modify critical system files through the manipulation of hard link permissions. The implications are particularly severe in enterprise environments where Solaris 8 systems might be running with multiple users and complex file permission structures. The vulnerability can be leveraged to create persistent access vectors or to escalate privileges within the system, making it a serious concern for system administrators responsible for maintaining security boundaries.
System administrators and security professionals should implement immediate mitigations including updating to gzip version 1.3 or later, which contains the necessary patches to address this vulnerability. The recommended approach involves upgrading the Solaris 8 systems to ensure that the patched version of gzip is in place, eliminating the risk of unintended permission changes during compression operations. Additionally, organizations should implement strict access controls and monitoring for gzip execution, particularly when force flags are used, to prevent unauthorized exploitation of this vulnerability. The mitigation strategy should include regular security audits to identify potential hard link scenarios that could be exploited and implementing least privilege principles for gzip usage. Organizations should also consider implementing additional file system monitoring to detect unauthorized permission changes that might indicate exploitation attempts, as this vulnerability can be used in conjunction with other attack vectors to compromise system integrity. This issue aligns with CWE-276, which addresses improper file permissions, and can be mapped to ATT&CK technique T1068, which involves exploiting local system privileges for unauthorized access.
The vulnerability demonstrates how seemingly simple utility functions can introduce complex security implications in Unix-like systems. The interaction between file system hard link structures and compression utilities creates unexpected behavior that can be exploited by malicious users. This case highlights the importance of thorough security testing for system utilities and the potential for privilege escalation through indirect system manipulation. Security teams should consider this vulnerability as part of broader system hardening efforts, ensuring that all system utilities are properly patched and that file permission management is carefully monitored to prevent unauthorized access through such indirect methods. The issue underscores the need for comprehensive security testing that includes edge cases involving file system structures and utility interactions, particularly in legacy systems like Solaris 8 where such vulnerabilities might persist longer than in modern systems.