CVE-2019-14861 Explained : Impact and Mitigation

Samba versions prior to 4.9.17, 4.10.11, and 4.11.3 have a vulnerability related to the dnsserver RPC pipe, allowing for DNS records modification.

Understanding CVE-2019-14861

This CVE affects Samba versions prior to 4.9.17, 4.10.11, and 4.11.3, impacting the dnsserver RPC pipe functionality.

What is CVE-2019-14861?

The vulnerability in Samba versions allows authenticated users to create new DNS records, potentially leading to memory access issues and pointer manipulation.

The Impact of CVE-2019-14861

The vulnerability can result in unauthorized modification of DNS records and zones, potentially leading to memory access violations and pointer manipulation.

Technical Details of CVE-2019-14861

Samba versions prior to 4.9.17, 4.10.11, and 4.11.3 are affected by this vulnerability.

Vulnerability Description

The issue arises from the dnsserver RPC pipe, allowing authenticated users to create DNS records that can lead to memory access violations.

Affected Systems and Versions

Samba versions 4.x.x before 4.9.17
Samba versions 4.10.x before 4.10.11
Samba versions 4.11.x before 4.11.3

Exploitation Mechanism

When responding to DnssrvEnumRecords() or DnssrvEnumRecords2(), memory access issues can occur, potentially leading to unauthorized memory access.

Mitigation and Prevention

Immediate Steps to Take:

Apply vendor patches and updates promptly.
Monitor vendor advisories for security patches.
Restrict access to vulnerable systems. Long-Term Security Practices:
Regularly update and patch software.
Implement network segmentation to limit the impact of potential breaches.
Conduct regular security audits and assessments.
Educate users on secure practices.
Employ network monitoring and intrusion detection systems.
Backup critical data regularly.

Patching and Updates

Ensure all Samba installations are updated to versions 4.9.17, 4.10.11, or 4.11.3 to mitigate the vulnerability.