USN-4456-1: Dovecot vulnerabilities
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Ubuntu Security Notice USN-4456-1
August 12, 2020
dovecot vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
Summary:
Several security issues were fixed in Dovecot.
Software Description:
- dovecot: IMAP and POP3 email server
Details:
It was discovered that Dovecot incorrectly handled deeply nested MIME
parts. A remote attacker could possibly use this issue to cause Dovecot to
consume resources, resulting in a denial of service. (CVE-2020-12100)
It was discovered that Dovecot incorrectly handled memory when using NTLM.
A remote attacker could possibly use this issue to cause Dovecot to crash,
resulting in a denial of service. (CVE-2020-12673)
It was discovered that the Dovecot RPA mechanism incorrectly handled
zero-length messages. A remote attacker could possibly use this issue to
cause Dovecot to crash, resulting in a denial of service. (CVE-2020-12674)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 20.04 LTS:
dovecot-core 1:2.3.7.2-1ubuntu3.2
Ubuntu 18.04 LTS:
dovecot-core 1:2.2.33.2-1ubuntu4.6
Ubuntu 16.04 LTS:
dovecot-core 1:2.2.22-1ubuntu2.13
In general, a standard system update will make all the necessary changes.
References:
https://usn.ubuntu.com/4456-1
CVE-2020-12100, CVE-2020-12673, CVE-2020-12674
Package Information:
https://launchpad.net/ubuntu/+source/dovecot/1:2.3.7.2-1ubuntu3.2
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.33.2-1ubuntu4.6
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.22-1ubuntu2.13
A Dovecot security update has been released for Ubuntu Linux 20.04 LTS, 18.04 LTS, and 16.04 LTS.
