========================================================================= Ubuntu Security Notice USN-4456-2 August 17, 2020 dovecot vulnerabilities ========================================================================= A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 14.04 ESM Summary: Several security issues were fixed in Dovecot. Software Description: - dovecot: IMAP and POP3 email server Details: USN-4456-1 fixed several vulnerabilities in Dovecot. This update provides the corresponding update for Ubuntu 14.04 ESM. Original advisory 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 14.04 ESM: dovecot-core 1:2.2.9-1ubuntu2.6+esm3 In general, a standard system update will make all the necessary changes. References: https://usn.ubuntu.com/4456-2 https://usn.ubuntu.com/4456-1 CVE-2020-12100, CVE-2020-12673, CVE-2020-12674