[USN-4563-2] NTP vulnerability

==========================================================================
Ubuntu Security Notice USN-4563-2
April 20, 2021

ntp vulnerability
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.10
- Ubuntu 20.04 LTS

Summary:

NTP could be made to crash.

Software Description:
- ntp: Network Time Protocol daemon and utility programs

Details:

USN-4563-1 fixed a vulnerability in NTP. This update provides the
corresponding update for Ubuntu 20.04 LTS and Ubuntu 20.10.

Original advisory details:

 It was discovered that the fix for CVE-2018-7182 introduced a NULL pointer
 dereference into NTP. An attacker could use this vulnerability to cause a
 denial of service (crash).

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 20.10:
  ntp                             1:4.2.8p12+dfsg-3ubuntu4.20.10.1
  ntpdate                         1:4.2.8p12+dfsg-3ubuntu4.20.10.1
  sntp                            1:4.2.8p12+dfsg-3ubuntu4.20.10.1

Ubuntu 20.04 LTS:
  ntp                             1:4.2.8p12+dfsg-3ubuntu4.20.04.1
  ntpdate                         1:4.2.8p12+dfsg-3ubuntu4.20.04.1
  sntp                            1:4.2.8p12+dfsg-3ubuntu4.20.04.1

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-4563-2
  https://ubuntu.com/security/notices/USN-4563-1
  CVE-2019-8936

Package Information:
  https://launchpad.net/ubuntu/+source/ntp/1:4.2.8p12+dfsg-3ubuntu4.20.10.1
  https://launchpad.net/ubuntu/+source/ntp/1:4.2.8p12+dfsg-3ubuntu4.20.04.1