CVE-2020-15663 : Security Advisory and Response

A vulnerability in Mozilla products could allow arbitrary code execution with system privileges on Windows systems.

Understanding CVE-2020-15663

This CVE highlights a security issue in Firefox, Thunderbird, and Firefox ESR versions.

What is CVE-2020-15663?

If Firefox is installed in a user-writable directory on Windows, the Mozilla Maintenance Service may execute updater.exe with system privileges, potentially leading to arbitrary code execution.

The Impact of CVE-2020-15663

The vulnerability could allow an attacker to exploit an older bug and execute arbitrary code with system privileges on affected Windows systems.

Technical Details of CVE-2020-15663

This section provides more technical insights into the vulnerability.

Vulnerability Description

A downgrade attack on the Mozilla Maintenance Service could result in privilege escalation, enabling arbitrary code execution.

Affected Systems and Versions

Firefox < 80
Thunderbird < 78.2, Thunderbird < 68.12
Firefox ESR < 68.12, Firefox ESR < 78.2

Exploitation Mechanism

The vulnerability arises from executing updater.exe with system privileges in user-writable directories on Windows.

Mitigation and Prevention

Protect your systems from CVE-2020-15663 with these steps.

Immediate Steps to Take

Update affected products to versions that address the vulnerability.
Avoid installing Firefox in user-writable directories on Windows.

Long-Term Security Practices

Regularly update Mozilla products to the latest secure versions.
Implement least privilege access to limit potential damage from such vulnerabilities.

Patching and Updates

Apply patches and updates provided by Mozilla to fix the vulnerability.