[USN-4922-1] Ruby vulnerability

========================================================================== Ubuntu Security Notice USN-4922-1 April 20, 2021
ruby2.3, ruby2.5, ruby2.7 vulnerability ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 20.10 – Ubuntu 20.04 LTS – Ubuntu 18.04 LTS – Ubuntu 16.04 LTS
Ruby incorrectly handled XML documents.
Software Description: – ruby2.7: Object-oriented scripting language – ruby2.5: Object-oriented scripting language – ruby2.3: Object-oriented scripting language
Juho Nurminen discovered that the REXML gem bundled with Ruby incorrectly parsed and serialized XML documents. A remote attacker could possibly use this issue to perform an XML round-trip attack.
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 20.10: libruby2.7 2.7.1-3ubuntu1.3 ruby2.7 2.7.1-3ubuntu1.3
Ubuntu 20.04 LTS: libruby2.7 2.7.0-5ubuntu1.4 ruby2.7 2.7.0-5ubuntu1.4
Ubuntu 18.04 LTS: libruby2.5 2.5.1-1ubuntu1.9 ruby2.5 2.5.1-1ubuntu1.9
Ubuntu 16.04 LTS: libruby2.3 2.3.1-2~ubuntu16.04.16 ruby2.3 2.3.1-2~ubuntu16.04.16
In general, a standard system update will make all the necessary changes.
References: ubuntu.com/security/notices/USN-4922-1 CVE-2021-28965
Package Information: launchpad.net/ubuntu/+source/ruby2.7/2.7.1-3ubuntu1.3 launchpad.net/ubuntu/+source/ruby2.7/2.7.0-5ubuntu1.4 launchpad.net/ubuntu/+source/ruby2.5/2.5.1-1ubuntu1.9 launchpad.net/ubuntu/+source/ruby2.3/2.3.1-2~ubuntu16.04.16