CVE-2017-6463 : Security Advisory and Response

CVE-2017-6463, published on March 27, 2017, addresses a vulnerability in NTP versions prior to 4.2.8p10 and 4.3.x prior to 4.3.94. Remote authenticated users can exploit this issue to cause a denial of service by using an invalid setting in a :config directive.

Understanding CVE-2017-6463

This CVE entry highlights a specific vulnerability in NTP that can be exploited by authenticated remote users to disrupt the service.

What is CVE-2017-6463?

CVE-2017-6463 allows remote authenticated users to trigger a denial of service on NTP versions before 4.2.8p10 and 4.3.x before 4.3.94. The vulnerability arises from an incorrect setting in a :config directive, particularly concerning the unpeer option.

The Impact of CVE-2017-6463

The vulnerability enables authenticated remote users to crash the NTP daemon, leading to a denial of service condition on affected systems.

Technical Details of CVE-2017-6463

This section delves into the technical aspects of the CVE.

Vulnerability Description

The flaw in NTP versions prior to 4.2.8p10 and 4.3.x before 4.3.94 allows remote authenticated users to cause a denial of service by manipulating a :config directive, specifically related to the unpeer option.

Affected Systems and Versions

NTP versions before 4.2.8p10
NTP 4.3.x versions before 4.3.94

Exploitation Mechanism

The vulnerability is exploited by authenticated remote users through the use of an invalid setting in a :config directive, particularly in relation to the unpeer option.

Mitigation and Prevention

Protecting systems from CVE-2017-6463 involves taking immediate and long-term security measures.

Immediate Steps to Take

Apply patches provided by the NTP vendor promptly.
Monitor network traffic for any suspicious activity targeting NTP services.

Long-Term Security Practices

Regularly update NTP software to the latest version to mitigate known vulnerabilities.
Implement network segmentation to limit the impact of potential attacks on NTP services.
Conduct regular security assessments and audits to identify and address vulnerabilities.

Patching and Updates

Ensure that all NTP installations are updated to versions 4.2.8p10 or 4.3.94 to eliminate the vulnerability and enhance system security.