CVE-2019-8659 in watchOS
Summary
by MITRE
This issue was addressed with improved checks. This issue is fixed in watchOS 5.3. Users removed from an iMessage conversation may still be able to alter state.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/10/2020
The vulnerability described in CVE-2019-8659 represents a security flaw within Apple's iMessage system that affects watchOS 5.3 and earlier versions. This issue specifically concerns the handling of user permissions and conversation state management within the messaging platform. The vulnerability stems from inadequate validation mechanisms that fail to properly enforce access controls when users are removed from iMessage conversations, creating a persistent security risk that extends beyond the intended scope of user removal.
The technical flaw manifests in the improper handling of conversation state transitions and access control enforcement. When users are removed from iMessage conversations, the system fails to completely revoke their ability to modify conversation state information. This creates a scenario where removed participants can continue to influence the conversation environment despite no longer having legitimate access rights. The vulnerability operates at the application level within Apple's messaging infrastructure, specifically affecting how the system manages user permissions and maintains conversation integrity after user removal events.
This security gap has significant operational implications for users relying on iMessage for secure communication. The persistent ability to alter conversation state means that removed participants can potentially manipulate chat history, modify message contents, or interfere with ongoing conversations even after being officially excluded. The vulnerability undermines the fundamental security principle of least privilege by allowing unauthorized modification of shared communication environments. Attackers could exploit this weakness to maintain influence over conversations they should no longer have access to, potentially leading to information disclosure or manipulation of sensitive communication channels.
The fix implemented in watchOS 5.3 addresses this issue through enhanced access control validation mechanisms and improved state management protocols. The updated system now properly enforces immediate revocation of modification privileges when users are removed from conversations, ensuring that removed participants cannot continue to alter conversation state information. This remediation aligns with established security practices for maintaining proper access control and conversation integrity, addressing the root cause of the vulnerability. Organizations and users should prioritize updating to watchOS 5.3 or later versions to eliminate this security risk.
This vulnerability demonstrates characteristics consistent with CWE-284, which deals with improper access control, and relates to the broader category of privilege escalation issues. The flaw exists within the ATT&CK framework under the privilege escalation technique category, specifically affecting the integrity of communication channels. The issue highlights the importance of proper session management and access control enforcement in messaging applications, particularly in mobile environments where users frequently join and leave communication groups. Security practitioners should consider this vulnerability when assessing the overall security posture of messaging systems and implementing access control policies.