Telegram down: popular encrypted messenger service Telegram faced a severe distributed denial of service (DDoS) attack the company said today; although it appeared to have stabilised after beginning around midday GMT.

The Russia-founded, British Virgin Isles-registered company took to Twitter to reassure customers that their data was safe. Nobody appears to have claimed responsibility for the attack publicly yet – which lasted several hours – nor given a motive.

Telegram boasts over 200 million monthly users.

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A DDoS attack relies on multiple compromised computer systems to attack a target, such as a server or website to disrupt service or serve as a mask to hide more targeted intrusions into an organisation’s infrastructure.

A survey by security specialist Radware suggests the financial cost of a single successful cyberattack climbed to an average of $1.1 million (£857,000) in 2018, up a hefty 52 percent from the previous year’s survey. Tel Aviv-headquartered DDoS mitigation specialist Radware surveyed 790 individual r

Jake Moore, Cybersecurity Specialist at ESET said in an emailed statement: “Telegram and other privacy focused messaging apps are possibly victims of their own success. They are still relatively small in scale yet offering huge services and used by millions. These are the types of companies targeted by cyber criminals as they create the most havoc and create quite a stir.”

“Furthermore, private messaging apps have been much the focus over the last few months and as DDoS attacks cause quite a reaction, this makes it and other similar apps a target for attacks. Protection from DDoS attacks can cost huge amounts of money especially when trying to predict the probability that the company will be targeted. However, it is certain that these attacks are on the increase and any protection possible is necessary as it can have massive consequences.”

A Radware report earlier this year shows that trying to secure a ransom is the leading motive in most DDoS attacks. (Chart below).

Telegram did not immediately reply to a request for comment on what DDoS mitigation strategies or tools it has in place.

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