This apparent GWC url "http://udp-host-cache.com/gwc/" with IP "52.49.1.53" that appears sometimes as "Skulls 0.3.2c" and sometimes as "Cachechu 1.6" get inserted inside Cachechu urls list.
The domain udp-host-cache.com is reported by Firefox as malicious.
The IP belong to Amazon Technologies Inc.
The Amazon Cloud can be rented and it is often used by malicious people.
Edit: the site redirect to another url, that when scanned give this: https://www.virustotal.com/it/url/da...is/1459336622/ Edit2: Loading the url now doesn't appears a valid GWebCache, so I wonder how it get inserted; it appears only on Cachechu caches and not in other caches so it possibly use a Cachechu vulnerability or just targetting Cachechu. Edit3: The domain now point to the IP "195.22.26.248" that belong "ESOTERICA (VIA NET.WORKS Portugal - Tecnologias de Informa,cao, SA)" that resolve to https://www.anubisnetworks.com/
It is really ironic.