Denial of service in ntpd

1) Authentication Bypass by Spoofing

EUVDB-ID: #VU27395

Risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-11868

CWE-ID: CWE-290 - Authentication Bypass by Spoofing

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authentication and perform a denial of service (DoS) attack.

The vulnerability exists due to ntpd allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address, because transmissions are rescheduled even when a packet lacks a valid origin timestamp.A remote attacker can bypass authentication and block synchronization.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

ntp: 4.2.0 - 4.3.99

External links

http://support.ntp.org/bin/view/Main/NtpBug3592
http://bugzilla.redhat.com/show_bug.cgi?id=1716665

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.