A world-renowned French expert on cyberwarfare has withdrawn from a cybersecurity conference being held in Vancouver this week.

Eric Filiol was slated to give a presentation, titled Hacking 9/11, on Friday at the 14th annual CanSecWest in downtown Vancouver. His talk allegedly detailed cyberthreats to critical public infrastructure.

On Monday, however, Filiol announced on Twitter that he was dropping out of the conference out of fear his talk could tip off would-be criminals.

But that explanation does not sit well with some.

Indiana-based security blogger Steve Ragan suggested Filiol is being censored by U.S. and French authorities who felt his hacking research was too sensitive to be made public.

"In this particular instance, you've got a talk that's talking about theoretical attacks that could take place," said Ragan. "Well, so realistic are these theories that intelligence for both France and the United States freaked out. And they advised him against presenting this talk. And, of course, because he's a member of the military himself, he used his gut judgment and did so."

Ragan said it is also possible Filiol is self-censoring, given the intense scrutiny on leakers such as former U.S. National Security Agency contractor Edward Snowden.

"Now there's an extra layer of precaution and an extra level of examination that's going to go into any type of presentation, research, publication, anything — be it right, be it wrong — that impacts security or national security or infrastructure in any form. And it's only going to get worse because the whole Snowden thing opened a can of worms," he said.

A bit overblown

"On one hand, you had people having their eyes forcefully opened to the level of privacy violations and things going on around them," said Ragan. "But on another hand, you expose valuable data-collection assets from the government …. There will be people who won't give their talk for fear of being labelled another Snowden."

Still, conference organizer Dragos Ruiu said the censorship explanation is a bit overblown.

"I would call some of the reaction a little bit knee-jerk," he said. "It is 'Oh my god, the government's involved. Here comes the government with jackboots.' And I don't think that was the case at all here.

"I think that this is just a discussion and a review amongst the people that Eric works with, sort of a joint decision on their part, that this material might need to be studied a little bit further before shining a big spotlight on it."

The conference is being held March 12 to March 14 at the Sheraton Wall Centre.