CVE-2004-0485 in Mac OS X
Summary
by MITRE
The default protocol helper for the disk: URI on Mac OS X 10.3.3 and 10.2.8 allows remote attackers to write arbitrary files by causing a disk image file (.dmg) to be mounted as a disk volume.
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Analysis
by VulDB Data Team • 11/19/2024
The vulnerability described in CVE-2004-0485 represents a critical security flaw in the Mac OS X operating system's handling of disk URI protocol helpers. This issue affects versions 10.3.3 and 10.2.8, where the system's default protocol handler for disk URIs lacks proper validation mechanisms. When a malicious attacker crafts a specially formatted disk URI and convinces a user to access it, the system automatically attempts to mount the associated disk image file as a volume. The flaw stems from the absence of proper input sanitization and access control measures within the protocol helper implementation.
The technical exploitation of this vulnerability occurs through a combination of social engineering and protocol handler manipulation. Attackers can craft malicious disk URIs that point to specially crafted .dmg files designed to be automatically mounted when accessed. The protocol helper system in Mac OS X 10.3.3 and 10.2.8 does not properly validate the source or integrity of the disk image files, allowing attackers to potentially write arbitrary files to the system. This occurs because the system treats all disk URIs equally without verifying their legitimacy or ensuring proper mounting permissions. The vulnerability essentially allows attackers to bypass normal file system access controls and potentially gain unauthorized write access to the target system.
The operational impact of this vulnerability extends beyond simple file system manipulation. An attacker could potentially create malicious disk images that, when mounted, execute arbitrary code or establish persistent access points on the compromised system. This represents a significant escalation from a simple file write vulnerability to a potential system compromise vector. The attack requires user interaction to access the malicious URI, but once triggered, the system's automatic mounting behavior creates a window of opportunity for unauthorized system modifications. This vulnerability directly impacts the principle of least privilege by allowing unauthorized file system operations through legitimate system mechanisms.
Security mitigations for this vulnerability should focus on implementing proper input validation within protocol helpers and strengthening the disk image mounting process. System administrators should ensure that automatic mounting of external disk images is disabled or restricted to trusted sources only. The implementation should include signature verification mechanisms for disk images and proper access control enforcement during the mounting process. This vulnerability aligns with CWE-22, which addresses improper limitation of a pathname to a restricted directory, and represents a specific implementation of path traversal vulnerabilities within the context of disk image handling. Organizations should also consider implementing network-level controls to prevent access to potentially malicious disk URI resources and establish security policies that restrict automatic mounting of external storage devices.
The broader implications of this vulnerability demonstrate the importance of secure protocol handler implementations in operating systems. This flaw illustrates how seemingly benign system features can become attack vectors when proper security controls are not implemented. The vulnerability highlights the need for comprehensive security testing of protocol helpers and automatic system behaviors that could be exploited by malicious actors. From an att&ck perspective, this vulnerability maps to initial access and privilege escalation techniques, as attackers can use it to establish a foothold and potentially gain elevated system privileges. Proper system hardening and user education regarding suspicious URI access are essential components of a comprehensive defense strategy against this type of attack vector.