CVE-2019-8656 Explained : Impact and Mitigation

Gatekeeper in macOS prior to version 10.14 has a vulnerability that allows bypassing security measures when extracting a zip file containing a symbolic link to an attacker-controlled NFS mount.

Understanding CVE-2019-8656

Gatekeeper in macOS versions less than 10.14 is susceptible to a security bypass issue when handling symbolic links in zip files.

What is CVE-2019-8656?

Gatekeeper in macOS is vulnerable to a specific attack vector involving symbolic links in zip files that can lead to a security bypass.

The Impact of CVE-2019-8656

The vulnerability allows attackers to bypass Gatekeeper's protection by exploiting symbolic links in zip files, potentially leading to unauthorized access and security breaches.

Technical Details of CVE-2019-8656

Gatekeeper vulnerability details and affected systems.

Vulnerability Description

Gatekeeper in macOS versions less than 10.14 fails to adequately handle symbolic links in zip files, enabling attackers to bypass security measures.

Affected Systems and Versions

Product: macOS
Vendor: Apple
Versions Affected: Less than 10.14

Exploitation Mechanism

Attackers can exploit the vulnerability by extracting a zip file containing a symbolic link to an endpoint in an attacker-controlled NFS mount, circumventing Gatekeeper's security checks.

Mitigation and Prevention

Steps to mitigate and prevent exploitation of CVE-2019-8656.

Immediate Steps to Take

Update macOS to version 10.14 or higher to address the vulnerability.
Avoid extracting zip files from untrusted sources.

Long-Term Security Practices

Regularly update your operating system and security patches.
Exercise caution when handling files from unknown or untrusted sources.

Patching and Updates

Apply Security Update 2019-004 for High Sierra and Sierra to fix the vulnerability in older macOS versions.