Ubuntu 23.10: USN-6657-1 Critical Dnsmasq Denial of Service

A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 23.10 - Ubuntu 22.04 LTS - Ubuntu 20.04 LTS Summary: Several security issues were fixed in Dnsmasq. Software Description: - dnsmasq: Small caching DNS proxy and DHCP/TFTP server Details: Elias Heftrig, Haya Schulmann, Niklas Vogel, and Michael Waidner discovered that Dnsmasq icorrectly handled validating DNSSEC messages. A remote attacker could possibly use this issue to cause Dnsmasq to consume resources, leading to a denial of service. (CVE-2023-50387) It was discovered that Dnsmasq incorrectly handled preparing an NSEC3 closest encloser proof. A remote attacker could possibly use this issue to cause Dnsmasq to consume resources, leading to a denial of service. (CVE-2023-50868) It was discovered that Dnsmasq incorrectly set the maximum EDNS.0 UDP packet size as required by DNS Flag Day 2020. This issue only affected Ubuntu 23.10. (CVE-2023-28450)