CVE-2017-7063 in watchOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 10.3.3 is affected. watchOS before 3.2.3 is affected. The issue involves the "Messages" component. It allows remote attackers to cause a denial of service (memory consumption and application crash).
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Analysis
by VulDB Data Team • 01/04/2021
The vulnerability identified as CVE-2017-7063 represents a significant security flaw within Apple's messaging ecosystem affecting multiple operating systems including iOS versions prior to 10.3.3 and watchOS versions prior to 3.2.3. This issue specifically targets the Messages component which serves as Apple's primary instant messaging platform integrating with iMessage and SMS functionality across their device ecosystem. The vulnerability manifests through a memory consumption attack that can be remotely exploited by adversaries to disrupt normal messaging operations and potentially compromise user communication channels.
The technical nature of this vulnerability falls under the category of resource exhaustion attacks where malicious actors can craft specially formatted messages that trigger excessive memory allocation within the Messages application. When these crafted messages are received by vulnerable devices, the application consumes increasing amounts of system memory until it becomes unresponsive or crashes entirely. This behavior aligns with CWE-400 which classifies improper resource management as a fundamental weakness in software systems, particularly when applications fail to properly handle resource allocation and deallocation in response to malformed inputs. The vulnerability demonstrates how seemingly benign communication protocols can be weaponized to create denial of service conditions that disrupt user experience and potentially provide cover for more sophisticated attacks.
From an operational perspective, this vulnerability presents a substantial risk to users who rely on messaging services for both personal and professional communication. The remote exploitation capability means that adversaries do not require physical access to devices or complex network positioning to deliver attacks, making the vulnerability particularly dangerous in mobile environments where users frequently receive messages from unknown or untrusted sources. The impact extends beyond simple application crashes to potentially disrupting critical communication channels, especially in enterprise environments where iMessage integration with business workflows may be prevalent. Attackers could leverage this vulnerability to repeatedly crash messaging applications, forcing users to restart devices or disable messaging services entirely, thereby creating a persistent disruption to communication infrastructure.
The security implications of CVE-2017-7063 align with ATT&CK technique T1499 which encompasses denial of service attacks targeting application availability. This vulnerability represents a classic example of how mobile messaging platforms can be targeted to create persistent availability issues, potentially serving as a stepping stone for more advanced attacks or simply causing inconvenience to users. Organizations implementing security controls should consider this vulnerability as part of their broader mobile device management strategies, particularly when evaluating the risk of message-based attacks in environments where communication reliability is critical. The remediation approach involves updating affected systems to versions that include patches addressing the memory management issues within the Messages component, with Apple releasing updates specifically targeting this vulnerability in their respective software releases.