========================================================================== Ubuntu Security Notice USN-4374-1 May 27, 2020 unbound vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 20.04 LTS - Ubuntu 19.10 - Ubuntu 18.04 LTS Summary: Several security issues were fixed in Unbound. Software Description: - unbound: validating, recursive, caching DNS resolver Details: Lior Shafir, Yehuda Afek, and Anat Bremler-Barr discovered that Unbound incorrectly handled certain queries. A remote attacker could use this issue to perform an amplification attack directed at a target. (CVE-2020-12662) It was discovered that Unbound incorrectly handled certain malformed answers. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service. (CVE-2020-12663) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 20.04 LTS: libunbound8 1.9.4-2ubuntu1.1 unbound 1.9.4-2ubuntu1.1 Ubuntu 19.10: libunbound8 1.9.0-2ubuntu1.1 unbound 1.9.0-2ubuntu1.1 Ubuntu 18.04 LTS: libunbound2 1.6.7-1ubuntu2.3 unbound 1.6.7-1ubuntu2.3 In general, a standard system update will make all the necessary changes. References: https://usn.ubuntu.com/4374-1 CVE-2020-12662, CVE-2020-12663 Package Information: https://launchpad.net/ubuntu/+source/unbound/1.9.4-2ubuntu1.1 https://launchpad.net/ubuntu/+source/unbound/1.9.0-2ubuntu1.1 https://launchpad.net/ubuntu/+source/unbound/1.6.7-1ubuntu2.3