Saturday, October 24, 2009

Eek! UPC doing awful DNS hijack thing!

UPC (formerly NTL Ireland and Chorus) is an Irish cable TV and Internet access provider. They're generally okay. They've just done something slightly irritating, though; if you ask their DNS to resolve an non-existent hostname, it does not, as you might reasonably expect, tell you it doesn't exist; instead, it says it does exist, and resolves it to a UPC search page, searching through Google or something for the domain name, with ads and so on.

Observe. A normal DNS server dealing with a non-existent domain:

Screen shot 2009-10-24 at 20.12.45.png

UPC's DNS server dealing with a non-existent domain:

Screen shot 2009-10-24 at 20.13.07.png

... And the awful consequences:

Screen shot 2009-10-24 at 20.13.34.png

This isn't just irritating money-grubbing on UPC's part; it also has the potential to be a real problem for some people. In particular, some VPN systems use various DNS tricks to figure out when they should activate; this could break them. Various other issues exist. There is also no clear way to turn it off. Ugh, what's next, inserting their own ads into webpages viewed? One US ISP actually does this.
Posted by Robert Synnott at 8:24 PM
Labels: , ,

2 comments:

  1. UPC have opt-out instructions on their site (in gloriously unnecessary PDF format). It involves changing the DNS servers to be used on the computer or router to 89.101.160.8 / 89.101.160.9.
    ReplyDelete
  2. I use a greasemonkey script to skip the page. It doesn't solve issues like VPN but it saves me having to change a bunch of settings everytime I change network. I made it available here:

    http://iolopearse.com/?p=161
    ReplyDelete

Subscribe to: Post Comments (Atom)