CVE-2019-6224 in macOS
Summary
by MITRE
A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 12.1.3, macOS Mojave 10.14.3, tvOS 12.1.2, watchOS 5.1.3. A remote attacker may be able to initiate a FaceTime call causing arbitrary code execution.
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Analysis
by VulDB Data Team • 01/05/2025
The vulnerability identified as CVE-2019-6224 represents a critical buffer overflow flaw in Apple's FaceTime implementation that could be exploited by remote attackers to achieve arbitrary code execution on targeted devices. This security weakness specifically affects the handling of memory during FaceTime call initiation processes, creating an exploitable condition that allows malicious actors to craft specially crafted calls that trigger memory corruption. The vulnerability stems from insufficient bounds checking and inadequate memory management practices within the FaceTime framework, which processes incoming call requests and manages the associated data structures. The flaw manifests when a remote attacker constructs a malicious FaceTime invitation that contains oversized data payloads, leading to buffer overflow conditions that can be leveraged to overwrite critical memory locations.
The technical exploitation of CVE-2019-6224 aligns with common software security patterns that fall under CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which addresses heap-based buffer overflow scenarios. The vulnerability operates through the FaceTime protocol implementation where incoming call data is processed without proper validation of buffer boundaries, allowing an attacker to exceed allocated memory space and potentially overwrite adjacent memory regions. This type of memory corruption can lead to unpredictable behavior including application crashes, data corruption, or more critically, the execution of arbitrary code within the context of the FaceTime process. The attack vector is particularly concerning as it requires no user interaction beyond accepting a FaceTime call, making it a prime candidate for social engineering attacks where victims might unknowingly accept malicious invitations.
From an operational security perspective, this vulnerability presents significant risk to enterprise and individual users alike, as it enables remote code execution without requiring physical access or user authentication. The attack model follows the typical remote exploitation pattern described in MITRE ATT&CK framework under technique T1059 for command and control execution, where an attacker can gain persistent access to devices through the initial buffer overflow exploit. The impact extends beyond simple privilege escalation as the vulnerability can be leveraged to install malicious applications, exfiltrate data, or establish persistent backdoors within the affected systems. Organizations with mobile device management policies must consider this vulnerability as a critical threat requiring immediate attention, particularly in environments where FaceTime is actively used for business communications.
The remediation for CVE-2019-6224 was addressed through Apple's security updates released in iOS 12.1.3, macOS Mojave 10.14.3, tvOS 12.1.2, and watchOS 5.1.3, which implemented improved memory handling and enhanced input validation mechanisms. Security practitioners should prioritize deployment of these updates across all affected platforms, particularly in enterprise environments where mobile device security is paramount. Additional mitigations include implementing network segmentation to limit FaceTime traffic, configuring firewall rules to restrict FaceTime service access, and monitoring for suspicious FaceTime call patterns that might indicate exploitation attempts. The vulnerability also highlights the importance of regular security assessments and vulnerability management programs that can identify similar memory corruption issues in other applications and services. Organizations should conduct comprehensive security testing of their mobile device configurations to ensure proper patch deployment and validate that the security fixes have been effectively applied to prevent exploitation of this and similar vulnerabilities.