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Eircom’s “DDOS”, or not

I woke up this morning to hear speculation on RTE Radio as to how Eircom’s DDOS woes were possibly being caused by the Russian mob, of all things. This absurd speculation is not helped by lines in statements like this:

‘The company blamed the problems on “an unusual and irregular volume of internet traffic” directed at its website, which affected the systems and servers that provide access to the internet for its customers.’

I’m speculating, too, but it seems a lot more likely to me that this isn’t just a DDOS, and someone — possibly just a lone Irish teenager — is running an attempted DNS cache-poisoning attack. Here’s why.

Last week, there were two features of the attack in reports: DDOS levels of traffic and incorrect pages coming up for some popular websites. To operate a Kaminsky DNS cache-poisoning attack requires buckets of packets — easily perceivable as DDOS levels. This level of traffic would be the first noticeable symptom on Eircom’s network management consoles, so it’d be easy to jump to the conclusion that a simple DDOS attack was the root cause.

This week, there’s just the DDOS levels of traffic. No cache poisoning effects have been reported. This would be consistent with Eircom’s engineers getting the finger out over the weekend, and upgrading the NSes to a non-vulnerable version. ;)

Once the attacker(s) realise this, they’ll probably stop the attack.

It’s not even a good attack for a bad guy to make, by the way. Given the timing, right after major press about a North Korean DDOS on US servers. it’s extremely high-profile, and made the news in several national newspapers (albeit in rather inept fashion). If someone wanted to make money from an attack, a massive-scale packet flood indistinguishable from a DDOS against the nation’s largest ISP is not exactly a subtle way to do it.

In the meantime, apparently OpenDNS have really seen the effects, with mass switchover of Eircom’s customers to the OpenDNS resolvers. Probably just as well…