This indicates an attack attempt to exploit an Out of Bounds Write Vulnerability in Dnsmasq.
The vulnerability occurs while extracting domain name of a RR record using the extract_name() function while sorting multiple RR records. A remote, unauthenticated attacker can run a server to send a specially crafted DNS reply to a target server. Successful exploitation leads to denial-of-service conditions or in worst case arbitrary code execution with administrative privileges.
Dnsmasq Dnsmasq prior to 2.83
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.