Ubuntu Security Notice USN-3951-1

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Ubuntu Security Notice USN-3951-1
April 23, 2019

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

– Ubuntu 19.04
– Ubuntu 18.10

Summary:

Dovecot could be made to crash if it received specially crafted network
traffic.

Software Description:
– dovecot: IMAP and POP3 email server

Details:

It was discovered that the Dovecot JSON encoder incorrectly handled certain
invalid UTF-8 characters. A remote attacker could possibly use this issue
to cause Dovecot to repeatedly crash, resulting in a denial of service.

Update instructions:

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

Ubuntu 19.04:
dovecot-core 1:2.3.4.1-1ubuntu2.1

Ubuntu 18.10:
dovecot-core 1:2.3.2.1-1ubuntu3.3

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

References:
https://usn.ubuntu.com/usn/usn-3951-1
CVE-2019-10691

Package Information:
https://launchpad.net/ubuntu/+source/dovecot/1:2.3.4.1-1ubuntu2.1
https://launchpad.net/ubuntu/+source/dovecot/1:2.3.2.1-1ubuntu3.3