CVE-2019-1552 : Vulnerability Insights and Analysis

CVE-2019-1552, also known as 'Windows builds with insecure path defaults,' is a vulnerability in OpenSSL that affects versions 1.1.1, 1.1.0, and 1.0.2. The issue allows unauthorized users to modify OpenSSL's default configuration, introduce additional CA certificates, or alter existing engine modules due to insecure path defaults.

Understanding CVE-2019-1552

This vulnerability arises from OpenSSL's internal defaults for directory structures, impacting Windows builds due to assumptions of a Unix-like environment.

What is CVE-2019-1552?

OpenSSL versions 1.1.0 and 1.1.1 assume Unix-like paths for Windows builds, leading to world-writable sub-directories under 'C:/usr/local.' This misconfiguration enables unauthorized modifications to OpenSSL's configuration and certificates.

The Impact of CVE-2019-1552

The severity of this vulnerability is considered low due to its limited impact on affected deployments. However, unauthorized alterations to OpenSSL's configuration can pose security risks.

Technical Details of CVE-2019-1552

This section provides detailed technical insights into the vulnerability.

Vulnerability Description

The mingw configuration targets in OpenSSL versions 1.1.0 and 1.1.1 assume a Unix-like environment for Windows builds, resulting in world-writable sub-directories under 'C:/usr/local.' This allows unauthorized modifications to OpenSSL's default configuration.

Affected Systems and Versions

OpenSSL 1.1.1 (Fixed in version 1.1.1d, affected versions 1.1.1-1.1.1c)
OpenSSL 1.1.0 (Fixed in version 1.1.0l, affected versions 1.1.0-1.1.0k)
OpenSSL 1.0.2 (Fixed in version 1.0.2t, affected versions 1.0.2-1.0.2s)

Exploitation Mechanism

Unauthorized users can exploit the world-writable sub-directories under 'C:/usr/local' to modify OpenSSL's default configuration, introduce additional CA certificates, or alter existing engine modules.

Mitigation and Prevention

Protecting systems from CVE-2019-1552 requires immediate steps and long-term security practices.

Immediate Steps to Take

Update OpenSSL to the fixed versions: 1.1.1d, 1.1.0l, and 1.0.2t
Restrict access to OpenSSL's configuration directories
Regularly monitor and audit changes to OpenSSL's configuration

Long-Term Security Practices

Implement the principle of least privilege for directory permissions
Conduct regular security assessments and audits of OpenSSL configurations
Stay informed about OpenSSL security updates and best practices

Patching and Updates

Ensure timely patching and updates of OpenSSL to the fixed versions to mitigate the vulnerability.