CVE-2020-11868 : Security Advisory and Response

Ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address.

Understanding CVE-2020-11868

This CVE involves a vulnerability in ntpd that could be exploited by an off-path attacker to disrupt unauthenticated synchronization.

What is CVE-2020-11868?

The vulnerability in ntpd allows an attacker to block unauthenticated synchronization by sending a server mode packet with a spoofed source IP address, causing rescheduling of transmissions even without a valid origin timestamp.

The Impact of CVE-2020-11868

CVSS Base Score: 5.9 (Medium Severity)
Attack Vector: Network
Attack Complexity: High
Availability Impact: High
Confidentiality Impact: None
Integrity Impact: None
Privileges Required: None
User Interaction: None
Scope: Unchanged

Technical Details of CVE-2020-11868

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability in ntpd allows an off-path attacker to disrupt unauthenticated synchronization by manipulating server mode packets.

Affected Systems and Versions

Affected Versions: ntp before 4.2.8p14 and 4.3.x before 4.3.100

Exploitation Mechanism

The attacker can exploit this vulnerability by sending a server mode packet with a spoofed source IP address to block unauthenticated synchronization.

Mitigation and Prevention

Protecting systems from CVE-2020-11868 is crucial to maintaining security.

Immediate Steps to Take

Update ntp to version 4.2.8p14 or 4.3.100 to mitigate the vulnerability.
Monitor network traffic for any suspicious activity related to NTP.

Long-Term Security Practices

Regularly update and patch NTP software to the latest versions.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Apply security patches provided by the NTP project to address known vulnerabilities.