CVE-2022-34892 in Parallels
Summary
by MITRE • 07/18/2022
This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop Parallels Desktop 17.1.1. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the update machanism. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root. Was ZDI-CAN-16396.
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Analysis
by VulDB Data Team • 08/06/2022
The vulnerability identified as CVE-2022-34892 represents a critical privilege escalation flaw within Parallels Desktop version 17.1.1 that demonstrates the dangerous consequences of inadequate synchronization mechanisms in system update processes. This vulnerability operates under the principle that attackers must first establish a foothold with low-privileged access before attempting exploitation, aligning with common attack patterns documented in the attack chain framework. The flaw specifically resides within the update mechanism of the Parallels Desktop application, where insufficient locking mechanisms fail to prevent concurrent access to shared resources during critical operations. The absence of proper object locking creates a race condition scenario where multiple threads or processes can simultaneously access and modify the same resource without proper coordination. This fundamental design weakness enables an attacker who has already compromised a low-privileged user account to manipulate the update process and subsequently elevate their privileges to the root level.
The technical implementation of this vulnerability stems from the update mechanism's failure to enforce proper mutual exclusion when handling objects that require atomic operations. When Parallels Desktop performs update-related activities, the system should maintain exclusive access to critical components to prevent concurrent modifications that could lead to inconsistent states. However, the lack of appropriate locking mechanisms means that an attacker can potentially interfere with these operations by creating race conditions or by injecting malicious code during update execution. This flaw directly maps to CWE-362, which describes a race condition vulnerability where two or more threads or processes access shared resources concurrently without proper synchronization. The attack vector requires an initial compromise of a low-privileged user account, which aligns with the concept of privilege escalation techniques commonly referenced in attack frameworks such as the MITRE ATT&CK matrix under the privilege escalation category. The exploitation process leverages the update mechanism's inherent weakness to manipulate system files or processes that are typically protected from modification by non-privileged users.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it fundamentally compromises the integrity and security posture of systems running affected Parallels Desktop versions. Once successfully exploited, attackers can execute arbitrary code with root privileges, effectively providing them with complete control over the compromised system. This level of access enables the attacker to install persistent backdoors, modify system configurations, exfiltrate sensitive data, or establish further footholds within network environments. The vulnerability's presence in the update mechanism is particularly concerning because updates are typically expected to be secure operations that maintain system integrity rather than create new attack surfaces. The exploitation process essentially transforms a legitimate system maintenance function into a vector for unauthorized system compromise, undermining the trust model that users place in software update processes. Organizations running affected versions face significant risk as this vulnerability can be exploited without requiring specialized knowledge of the system internals, making it particularly dangerous in enterprise environments where multiple users may have access to the system.
Mitigation strategies for CVE-2022-34892 should focus on immediate patching of the affected Parallels Desktop installations to address the underlying locking mechanism deficiencies. System administrators should prioritize updating to version 17.1.2 or later, which contains the necessary fixes for the race condition vulnerability. Additionally, organizations should implement monitoring of update processes and file system changes during update operations to detect potential exploitation attempts. The remediation approach aligns with standard security practices for addressing race condition vulnerabilities, including the implementation of proper synchronization primitives and access controls. Network segmentation and privilege reduction measures can help limit the potential impact if exploitation occurs, while regular security assessments should be conducted to identify similar vulnerabilities in other system components. The fix implemented by Parallels Desktop likely involves adding proper locking mechanisms to ensure that update operations are atomic and that concurrent access to shared resources is properly managed. This vulnerability serves as a reminder of the critical importance of secure coding practices, particularly in system-level operations where concurrency and resource management play crucial roles in maintaining system security. The incident highlights the need for comprehensive security testing of update mechanisms and the importance of considering race conditions as part of the threat modeling process for system software components.