A malicious attacker deliberately attempted to interfere with a crucial party leadership vote in Canada last month, according to a company commissioned to run the online voting system used.

Scytl Canada, which provides online balloting services, confirmed that a deliberate denial of service attack was launched in an attempt to disrupt the federal NDP leadership vote on March 24.

Over 10,000 separate computers were used in the denial-of-service  (DoS) attack, which began during the second round of balloting, which began at 11 a.m.. Reports of timeouts on the system caused operators to examine the logs, identifying and external attack.

Scytl increased system throughput and blocked malevolent IP addresses, and managed to keep the system running at a slower speed.

“By keeping ahead of the attackers, Scytl was able to allow the voting process to proceed with an overall three-hour delay,” the company said.

The attackers used a botnet with compromised machines located mainly in Canada, the company said after research. “The required organization and demonstrated orchestration of the attack indicates that this was a deliberate effort to disrupt or negate the election by a knowledgeable person or group,” it said in a statement.
The NDP leadership election was held following the death of former leader Jack Layton in August.