CVE-2010-0055 in Mac OS X
Summary
by MITRE
xar in Apple Mac OS X 10.5.8 does not properly validate package signatures, which allows attackers to have an unspecified impact via a modified package.
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Analysis
by VulDB Data Team • 05/03/2026
The vulnerability identified as CVE-2010-0055 resides within the xar package manager component of Apple Mac OS X version 10.5.8, representing a critical security flaw in the operating system's package validation mechanisms. This issue stems from insufficient signature validation procedures that fail to properly verify the authenticity and integrity of package contents. The xar utility serves as a fundamental packaging tool in macOS environments, responsible for creating and extracting package archives that contain software installations and system updates. When the system processes packages without adequate signature verification, it creates a pathway for malicious actors to manipulate package contents while maintaining apparent legitimacy within the system's trust model.
The technical implementation of this vulnerability manifests through the failure of the xar utility to enforce proper cryptographic signature validation during package processing. This weakness allows attackers to modify package contents, potentially injecting malicious code or altering existing components without triggering security warnings. The flaw operates at the package management layer, where the system should validate digital signatures using established cryptographic mechanisms before executing package installation routines. Without proper validation, the system accepts modified packages as legitimate, bypassing the security controls designed to prevent unauthorized modifications. This type of vulnerability falls under the CWE-311 category of Missing Encryption of Sensitive Data, specifically affecting the integrity verification mechanisms within the software supply chain. The impact extends beyond simple code injection, as it undermines the entire package trust model that macOS relies upon for secure software distribution.
The operational consequences of CVE-2010-0055 create significant risks for macOS users and system administrators who depend on the integrity of package management processes. Attackers could exploit this vulnerability to deliver malicious payloads through seemingly legitimate software updates or installations, potentially compromising entire systems without detection. The unspecified impact designation reflects the broad range of possible attack vectors and damage scenarios that could occur, from privilege escalation to complete system compromise. This vulnerability particularly affects environments where automated package deployment occurs, as modified packages could propagate through networked systems without triggering security alerts. The attack surface expands when considering that xar is used for both user-installed applications and system-level packages, making it a critical target for exploitation. According to ATT&CK framework category T1554, this vulnerability aligns with the technique of Establishing Persistence through package management tools, as attackers could modify legitimate package contents to maintain access or deploy malicious code.
Mitigation strategies for CVE-2010-0055 require immediate system updates and enhanced monitoring of package management activities. Apple addressed this vulnerability through subsequent security updates that strengthened signature validation mechanisms within the xar utility. System administrators should implement comprehensive package integrity monitoring, regularly verifying package signatures and contents against known good baselines. The implementation of additional security controls including code signing verification, integrity checks, and automated package scanning tools can help detect and prevent exploitation attempts. Organizations should also consider implementing network-level controls to monitor package distribution channels and ensure that only authenticated packages are processed. The vulnerability highlights the importance of maintaining up-to-date systems and proper security hygiene in preventing supply chain attacks that leverage package management flaws. Regular security audits of package management configurations and enforcement of strict access controls for package creation and modification processes further reduce the risk of exploitation.