CVE-2014-8831 in Mac OS X
Summary
by MITRE
security_taskgate in Apple OS X before 10.10.2 allows attackers to read group-ACL-restricted keychain items of arbitrary apps via a crafted app with a signature from a (1) self-signed certificate or (2) Developer ID certificate.
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Analysis
by VulDB Data Team • 12/16/2024
The vulnerability identified as CVE-2014-8831 represents a critical privilege escalation flaw in Apple's macOS operating system affecting versions prior to 10.10.2. This issue resides within the security_taskgate component which governs access controls and privilege boundaries within the system's security architecture. The vulnerability specifically targets the keychain access control mechanisms that are designed to protect sensitive authentication data and credentials stored within the system's secure storage. The flaw enables malicious actors to bypass normal access controls that should prevent unauthorized applications from accessing keychain items that are restricted to specific groups or access control lists.
The technical implementation of this vulnerability exploits the trust model inherent in macOS security architecture where applications can be signed with either self-signed certificates or Developer ID certificates. When an attacker crafts a malicious application using either of these certificate types, the security_taskgate component fails to properly validate the access permissions of the requesting application against the target keychain items. This allows the malicious application to enumerate and read keychain entries that should only be accessible to specific groups or applications with appropriate clearance levels. The vulnerability essentially creates a pathway for unauthorized access to sensitive authentication data that could include passwords, encryption keys, and other critical security credentials stored in the keychain.
The operational impact of this vulnerability extends beyond simple information disclosure as it provides attackers with access to authentication credentials that could be used for further exploitation within the compromised system. Attackers could leverage this access to obtain credentials for various online services, network resources, and system accounts that are protected by the keychain's access control mechanisms. The vulnerability affects all applications running on affected macOS versions and can be exploited by any malicious application that successfully signs itself with either a self-signed certificate or Developer ID certificate, making it particularly dangerous as it does not require special privileges or complex attack vectors.
This vulnerability aligns with CWE-284, which describes improper access control issues in software systems, and demonstrates how inadequate privilege checking can lead to unauthorized access to protected resources. The attack pattern corresponds to techniques described in the ATT&CK framework under privilege escalation and credential access domains, where adversaries seek to obtain credentials that can be used to access additional systems or data. The security_taskgate component's failure to properly enforce access controls creates a persistent risk that remains active until the system is updated to a patched version, making it a particularly concerning vulnerability for enterprise environments where macOS systems are widely deployed.
The recommended mitigation strategy involves immediate deployment of macOS 10.10.2 or later updates that contain the necessary patches to address the security_taskgate implementation. Organizations should also implement monitoring for suspicious application signatures and access patterns that might indicate exploitation attempts. Additionally, system administrators should consider implementing additional security controls such as application whitelisting policies and enhanced monitoring of keychain access patterns to detect potential exploitation attempts. The vulnerability highlights the importance of proper certificate validation and access control enforcement in operating system security architectures, particularly when dealing with sensitive credential storage mechanisms that are fundamental to system security.