CSIS website falls victim to yet another cyberattack

The websiteof Canada's spy agency, CSIS, wasoffline for several hours again Tuesdayafter a cyberattack shut it down for the third time in twodays.

"Good night again CSIS," was posted by Twitteruser @TWITRis4tards, an account linked to a person or group called Aerithclaimingresponsibility for previous attacks. "I seriously need to teach CSIS network security," the tweet said.

CSIS's website was back upas of 10 p.m. ET. It went offline in the late afternoon.

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Earlier Tuesday, aspokesmanfor Public Safety Minister Steven Blaneysaidno data had beencompromised.

"No information was breached," saidJeremy Laurin in an emailto CBC News. "We are taking cyber security very seriously."

It's not yet clear if the same holds true for this latestattack.

The Twitter user alsoposted further messages, including a threat for more possible action on Wednesday.

"I got a plan for Canada Day. I hope no one wants to sendemailtomorrow who works for govt."

These denial of service attacks comeon the heels of similar attacks two weeks ago on websites for the Senate, the Justice Department, CSIS and Canada's electronic spy agency, CSEC.

The online hacker group Anonymous had claimed responsibility for those earlier incidents toprotest the recent passing of the government's anti-terror legislation,Bill C-51.

'Aerith' claims responsibility

Aerithhad claimedresponsibility for Monday's attack and Tuesday's earlier attackon theCSISwebsite, as well as an attack on the Conservative Party's website. Conservative.ca is now online again.

"Yes I did the attacks. I have more planned," said Aerithin an email to CBC News.

As for a motive, Aerithsaid the government'santi-terror Bill C-51wasone reason, as was the trialof a 17-year-old Ottawa boy accused of making a series of fake 911 calls in Canada and the U.S., a practice known as swatting.

"He's been framed," Aerithsaid in an email. "I've shown evidence before and it's fallen on deaf ears. So I'll just get louder. Further attacks will be, we have something bigger planned."

Aerith has alsoclaimed responsibility for taking down Toronto and Ottawa police websitesin the past.

Denial of service attacks easy to do

Experts say denial of service attacks do not require expert technological skill or knowledgeand they are fairly easy to defend against. The CSIS website, while symbolic, does not holdconfidential information and is not a service website for the public, so its defence might be a low priority for the government.

"So it being down isn't really affecting Canadians at all," said Patrick Malcolm of Ottawa-based cyber-security company Netrunner in an interview with CBC News. "So as a result, I wouldn't put too many security dollars into that bin. I've got other systems I'd be more concerned about [if I werethe government]."

But Malcolm saiddenial of service attacks can serve assmokescreens for more nefarious acts such as a real hack of the system in an attempt to steal information or disrupt service.