CVE-2020-12244 : Exploit Details and Defense Strategies

PowerDNS Recursor 4.1.0 through 4.3.0 is affected by a vulnerability that allows an attacker to bypass DNSSEC validation.

Understanding CVE-2020-12244

This CVE involves a specific issue in PowerDNS Recursor versions 4.1.0 through 4.3.0 that impacts the validation of records in the answer section of a NXDOMAIN response.

What is CVE-2020-12244?

An issue in PowerDNS Recursor versions 4.1.0 through 4.3.0 allows an attacker to bypass DNSSEC validation by exploiting improper validation of records in the answer section of a NXDOMAIN response.

The Impact of CVE-2020-12244

This vulnerability could be exploited by an attacker to bypass DNSSEC validation, potentially leading to unauthorized access or DNS spoofing attacks.

Technical Details of CVE-2020-12244

PowerDNS Recursor 4.1.0 through 4.3.0 is susceptible to the following technical details:

Vulnerability Description

The issue lies in the improper validation of records in the answer section of a NXDOMAIN response in PowerDNS Recursor, specifically in the SyncRes::processAnswer function.

Affected Systems and Versions

Versions affected: 4.1.0 through 4.3.0
Systems: PowerDNS Recursor

Exploitation Mechanism

The vulnerability allows an attacker to exploit the lack of proper validation in the SyncRes::processAnswer function, enabling them to bypass DNSSEC validation.

Mitigation and Prevention

To address CVE-2020-12244, consider the following mitigation strategies:

Immediate Steps to Take

Update PowerDNS Recursor to a non-vulnerable version.
Monitor for any unauthorized access or DNS spoofing activities.

Long-Term Security Practices

Regularly update and patch PowerDNS Recursor to prevent known vulnerabilities.
Implement DNSSEC to enhance DNS security.

Patching and Updates

Apply patches provided by PowerDNS to fix the vulnerability.