​Encrypted email firm ProtonMail stiffed after paying DDoS ransom

  • Liam Tung (CSO Online)
  • 06 November, 2015 09:09

Switzerland-based encrypted email provider ProtonMail provider says a payment to stop attackers overloading its network didn’t work. Now it's appealing to the public to fund its "top-of-line" DDoS protection provider.

The privacy-focussed email provider, which crowd-funded its 2014 launch in the wake of Edward Snowden’s disclosures, was knocked offline on Tuesday by what it said was an “extremely powerful” distributed denial of service (DDoS) attack.

The company today detailed its two day ordeal with the attack, explaining to users that it began with an extortion email from a group that’s been targeted Swiss firms over the past month.

ProtonMail pointed to a warning in September from Switzerland’s GovCERT that a group known as “Armada Collective” had targeted Swiss hosting providers in recent weeks with demands of 10 Bitcoin, equivalent at the time to US $2500 with the currency’s recent rise in value is today worth over $4,000.

Swiss CERT recommended victims not pay the group and instead talk to their ISP about mitigation plans.

Later on Tuesday ProtonMail was served the attacker’s signature 15 minute “demo DDoS”, which, according to Swiss CERT, is done to show the threat is credible, at a volume large enough to rattle but not disable a target’s network.

The attack began in earnest at 11am on Wednesday at which point the firm and its ISP bunkered down to weather the assault.

However, within hours the attacks took on an “unprecedented level of sophistication” and by 2pm the speed of the attack against ProtonMail’s ISP exceeded 100Gbps. There have been larger attacks, but according to ProtonMail, this was unprecedented in Switzerland and large enough to spill over knock out the ISP and hundreds of its clients.

That’s when ProtonMail said it decided “under a lot of pressure by third parties” to pay the ransom, which it did “grudgingly” to this bitcoin address, showing up on the Blockchain ledger as a payment of 15 BTC from ProtonMail, valued at $6,120.

Unfortunately for ProtonMail, the payment didn’t stop the attack and the company has now decided it’s necessary to pay for a DDoS protection service — costing upwards of $100,000 a year — that it can’t sustain.

In a strange twist to the ordeal, ProtonMail said the criminals that stiffed it later wrote to it denying responsibility for the second attack.

“The attack disrupted traffic across the ISP’s entire network and got so serious that the criminals who extorted us previously even found it necessary to write us to deny responsibility for the second attack,” it said.

There is a possibility that the criminal group was telling the truth. As ProtonMail explains the first attack was “volumetric” and only targeted its IP addresses, whereas the second “more complex” attack targeted its ISP’s infrastructure.

“This second phase has not been observed in any other recent attacks on Swiss companies and was technically much more sophisticated,” it said.

MELANI, a government agency which Switzerland’s GovCERT reports, is investigating the incident, however that doesn’t help ProtonMail’s financial predicament. To aid that effort, the firm is going back to its crowdfunding roots and has appealed to the public to support its “defense fund”, which is seeking to raise $50,000 to help its mission to protect privacy and help it pay for “top-of-the-line solutions typically used by large companies such as Twitter, Facebook, etc”

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