CVE-2021-1771 Explained : Impact and Mitigation
Learn about CVE-2021-1771, a macOS vulnerability allowing removed iMessage users to rejoin groups. Find impact, systems affected, exploitation, and mitigation steps.
macOS users were facing a vulnerability where a user removed from an iMessage group could rejoin after being removed. Apple addressed this issue with improved checks in macOS Big Sur 11.2 and Security Updates for Catalina and Mojave.
Understanding CVE-2021-1771
This CVE identifies a security flaw in macOS that allowed a user removed from an iMessage group to rejoin the group, posing a risk to group privacy and security.
What is CVE-2021-1771?
CVE-2021-1771 refers to the vulnerability in macOS that permitted a user to rejoin an iMessage group even after being removed, potentially compromising the security and privacy of the group.
The Impact of CVE-2021-1771
The impact of this vulnerability is significant as it allows expelled users to regain access to group conversations, potentially leading to unauthorized access to sensitive information shared within the group.
Technical Details of CVE-2021-1771
The technical details of CVE-2021-1771 include:
Vulnerability Description
The vulnerability allowed a user to rejoin an iMessage group even after being removed, indicating a flaw in the group management system.
Affected Systems and Versions
Affected systems include macOS versions below 11.2. Users running older versions were susceptible to this vulnerability.
Exploitation Mechanism
Exploiting this vulnerability involved leveraging the flaw in the iMessage group management system to circumvent the removal process and rejoin the group.
Mitigation and Prevention
To address CVE-2021-1771, consider taking the following measures:
Immediate Steps to Take
Users should update their macOS to version 11.2 or later to mitigate the risk of unauthorized rejoining of iMessage groups.
Long-Term Security Practices
Maintain regular system updates and security patches to prevent similar vulnerabilities from being exploited in the future.
Patching and Updates
Regularly check for and apply the latest security updates provided by Apple to ensure your system is protected from known vulnerabilities.