Debian LTS: DLA-3974-1 critical: dnsmasq denial of service

Brief introduction

CVE-2022-0934

A single-byte, non-arbitrary write/use-after-free flaw was found in dnsmasq.
This flaw allows an attacker who sends a crafted packet processed by
dnsmasq, potentially causing a denial of service.

CVE-2023-28450

An issue was discovered in Dnsmasq before 2.90. The default maximum EDNS.0
UDP packet size was set to 4096 but should be 1232 because of DNS Flag Day
2020.

CVE-2023-50387

Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840,
and related RFCs) allow remote attackers to cause a denial of service (CPU
consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One
of the concerns is that, when there is a zone with many DNSKEY and RRSIG
records, the protocol specification implies that an algorithm must evaluate
all combinations of DNSKEY and RRSIG records.

CVE-2023-50868

The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC