USN-4882-1: Ruby vulnerabilities

It was discovered that the Ruby JSON gem incorrectly handled certain JSON
files. If a user or automated system were tricked into parsing a specially
crafted JSON file, a remote attacker could use this issue to execute
arbitrary code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04
LTS. (CVE-2020-10663)

It was discovered that Ruby incorrectly handled certain socket memory
operations. A remote attacker could possibly use this issue to obtain
sensitive information. This issue only affected Ubuntu 18.04 LTS and
Ubuntu 20.04 LTS. (CVE-2020-10933)

It was discovered that Ruby incorrectly handled certain transfer-encoding
headers when using Webrick. A remote attacker could possibly use this issue
to bypass a reverse proxy. (CVE-2020-25613)