PlusServer has a PlusSized problem with Angler

PlusServer GmbH is a legitimate German hosting company. But unfortunately, the bad guys keep hosting Angler EK sites in their IP ranges over and over again.

So far I have seen many /24 blocks which have effectively been burned by out-of-control Angler (and other EK) infections. There are many individual IPs too, but below I list some of the worst blocks (links go to Pastebin).

85.25.102.0/24
85.25.107.0/24
85.25.160.0/24 
85.93.93.0/24
188.138.17.0/24
188.138.70.0/24 
188.138.71.0/24
188.138.75.0/24
188.138.102.0/24
188.138.105.0/24 
188.138.125.0/24 
217.172.189.0/24
217.172.190.0/24

Blocking these ranges will block some legitimate sites, but if Angler is causing you a problem then I would lean towards blocking those ranges and accepting the chance of some minor or moderate collateral damage. There are other bad ranges here for other hosts too.

UPDATE 2016-04-25

Here are some more PlusServer ranges where Angler has been rampant:

85.25.218.0/24
85.25.237.0/24
188.138.25.0/24
188.138.68.0/24

UPDATE 2016-05-10

Heavy Angler activity has also been spotted in the following ranges:

62.75.203.0/24
62.75.207.0/24
85.25.43.0/24 
85.25.79.0/24
85.25.159.0/24
85.25.217.0/24
188.138.33.0/24
188.138.68.0/24
188.138.125.0/24

In addition, some Angler activity has been observed in the following ranges but is not yet widespread (I will update if I see more activity):

62.75.167.0/24
85.25.41.0/24

85.25.74.0/24

85.25.106.0/24
85.25.207.0/24

188.138.41.0/24
188.138.57.0/24
188.138.69.0/24
188.138.102.0/24

PlusServer (or more likely one or more of their resellers) appear to be responsible for a large number of active Angler EK IPs (at a guesstimate, about a quarter). The problem is that some of these ranges are so badly infected (e.g. there are around 48 past and present bad IPs in 188.138.105.0/24) that the only safe option is to block traffic to those network ranges.

With black hat hosts such as Qhoster or Host Sailor and to some extent Agava you can block the entire network ranges and not block anything of value at all. In using PlusServer, the bad guys can hide their evil sites among legitimate sites where administration might fear to block something accidentally. My personal opinion is that admins need to be bold and block anyway.. it should usually be possible to block individual sites where needed.