CVE-2020-3891 Explained : Impact and Mitigation

A logic issue in iOS, iPadOS, and watchOS versions allowed unauthorized message responses on locked devices.

Understanding CVE-2020-3891

A logic issue was addressed in iOS, iPadOS, and watchOS to prevent unauthorized message responses on locked devices.

What is CVE-2020-3891?

CVE-2020-3891 is a logic issue in iOS, iPadOS, and watchOS that could enable a person with physical access to a locked iOS device to respond to messages even when replies are disabled.

The Impact of CVE-2020-3891

The vulnerability could potentially lead to unauthorized access to messages on locked iOS devices, compromising user privacy and security.

Technical Details of CVE-2020-3891

A logic issue was identified and fixed in the following versions:

Vulnerability Description

The issue allowed unauthorized message responses on locked iOS, iPadOS, and watchOS devices.

Affected Systems and Versions

iOS and iPadOS versions less than 13.4
watchOS versions less than 6.2

Exploitation Mechanism

Physical access to a locked iOS device was required to exploit the vulnerability.

Mitigation and Prevention

Steps to address and prevent the CVE-2020-3891 vulnerability:

Immediate Steps to Take

Update affected devices to iOS 13.4 and iPadOS 13.4, watchOS 6.2 or later versions.
Avoid leaving devices unattended to prevent unauthorized access.

Long-Term Security Practices

Enable device passcodes and biometric authentication for added security.
Regularly update devices to the latest software versions to patch known vulnerabilities.
Implement security measures to protect physical access to devices.

Patching and Updates

Apply security updates provided by Apple to ensure devices are protected against known vulnerabilities.