CVE-2004-1083 in Mac OS X
Summary
by MITRE
apache for apple mac os x 10.2.8 and 10.3.6 restricts access to files in a case sensitive manner but the apple hfs+ filesystem accesses files in a case insensitive manner which allows remote attackers to read .ds_store files and files beginning with ".ht" using alternate capitalization.
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Analysis
by VulDB Data Team • 06/02/2019
This vulnerability exists in Apache HTTP Server versions running on Apple Mac OS X 10.2.8 and 10.3.6 systems where there is a fundamental mismatch between the case-sensitive file access behavior of the Apache server and the case-insensitive nature of the Apple HFS+ filesystem. The Apache server implements case-sensitive file access controls, meaning it strictly enforces file name casing when determining access permissions and file existence. However, the underlying HFS+ filesystem used by Mac OS X operates in a case-insensitive manner, allowing files with different capitalizations to reference the same physical file on disk.
The security implications arise when attackers exploit this inconsistency to access sensitive files that should normally be protected. Specifically, the vulnerability allows remote attackers to read .DS_Store files and files beginning with ".ht" using alternate capitalization patterns. These file types often contain sensitive information including directory listings, system configuration details, and potentially authentication credentials. The .DS_Store files are Mac OS X metadata files that store directory attributes and can reveal internal directory structures, while .ht files typically represent HTTP server configuration files that may contain sensitive settings or authentication parameters.
This vulnerability represents a classic example of a filesystem-level inconsistency that creates security boundaries that can be bypassed through creative file naming. The flaw enables what is known as a case-insensitive file system traversal attack, where an attacker can enumerate and access files that would normally be protected by case-sensitive access controls. This type of vulnerability is categorized under CWE-227, which deals with improper handling of case sensitivity in file systems, and aligns with ATT&CK technique T1083 for discovering files and directories, as attackers can effectively bypass file access restrictions through capitalization manipulation.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can provide attackers with detailed knowledge of the server's directory structure and potentially sensitive configuration information. Attackers can leverage this to map the filesystem, identify protected directories, and potentially discover other vulnerabilities. The attack vector is particularly concerning because it requires no special privileges or complex exploitation techniques, relying instead on fundamental inconsistencies between operating system components. Organizations running Apache servers on Mac OS X systems were vulnerable to this attack, as it exploited the inherent mismatch between Apache's case-sensitive processing and HFS+'s case-insensitive storage mechanisms.
Mitigation strategies for this vulnerability involve addressing the fundamental inconsistency between the web server's access controls and the filesystem's behavior. System administrators should ensure that Apache configurations properly account for the underlying filesystem characteristics, potentially by implementing additional access controls or by upgrading to versions where this inconsistency has been resolved. The most effective approach involves either modifying the Apache server configuration to explicitly handle case-insensitive filesystems or upgrading to newer versions of both Apache and Mac OS X where this specific mismatch has been addressed. Additionally, implementing proper file permissions and access controls at the filesystem level can help reduce the exposure of sensitive files to unauthorized access. Organizations should also conduct regular security audits to identify and remediate similar inconsistencies between different system components that could create unexpected security boundaries.