This indicates an attack attempt to exploit a Memory Corruption Vulnerability in AVM FRITZ!Box.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted XML file. An unauthenticated attacker could exploit this to execute arbitrary code within the context of the application.
AVM FRITZ!Box with version 6.30 and prior
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.