CVE-2019-13951 Explained : Impact and Mitigation

A buffer overflow vulnerability exists in the set_ipv4() function of the zscan_rfc1035.rl file in gdnsd versions prior to 3.2.1. This vulnerability arises when processing zone data with long and improperly formatted IPv4 addresses.

Understanding CVE-2019-13951

This CVE identifies a stack-based buffer overflow in gdnsd versions before 3.2.1 due to handling malformed IPv4 addresses.

What is CVE-2019-13951?

The vulnerability in the set_ipv4() function of gdnsd allows attackers to trigger a buffer overflow by providing specially crafted IPv4 addresses in zone data.

The Impact of CVE-2019-13951

Exploitation of this vulnerability could lead to arbitrary code execution or denial of service (DoS) attacks on systems running affected gdnsd versions.

Technical Details of CVE-2019-13951

This section delves into the specifics of the vulnerability.

Vulnerability Description

The set_ipv4() function in gdnsd 3.x before 3.2.1 is susceptible to a stack-based buffer overflow when processing malformed IPv4 addresses in zone data.

Affected Systems and Versions

Vulnerable: gdnsd versions prior to 3.2.1
Unaffected: gdnsd 3.2.1 and later

Exploitation Mechanism

Attackers can exploit this vulnerability by providing long and improperly formatted IPv4 addresses in zone data, triggering the buffer overflow.

Mitigation and Prevention

Protecting systems from CVE-2019-13951 involves immediate actions and long-term security practices.

Immediate Steps to Take

Update gdnsd to version 3.2.1 or later to mitigate the vulnerability.
Monitor network traffic for any signs of exploitation.

Long-Term Security Practices

Regularly update software and apply security patches promptly.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Apply patches provided by gdnsd to address the buffer overflow vulnerability.