Hewlett-Packard's Zero Day Initiative (ZDI) yesterday spelled out the rules for its March hacking contest, Pwn2Own, which will put two-thirds of a million dollars in prize money on the table for researchers who can hack the biggest browsers and most popular plug-ins.

ZDI is HP's bug-bounty program, run by its TippingPoint division, a maker of intrusion prevention system (IPS) and firewall appliances for corporate networks.

The 2014 edition of Pwn2Own will offer $645,000 in potential awards to hackers who demonstrate exploits of previously-unknown vulnerabilities in Google's Chrome, Mozilla's Firefox, Microsoft's Internet Explorer (IE) or Apple's Safari, or the Adobe Reader, Adobe Flash or Oracle Java browser plug-ins.

Those targets were also the focus of last year's challenge.

Prizes will be awarded on a sliding schedule, with $100,000 for the first to hack Chrome or IE11 on Windows 8.1. Payments will drop to $75,000 for Adobe Flash or Reader running in IE11, then slide through other targets before ending at $30,000 for Java. Prizes will also be given for exploiting Safari ($65,000) and Firefox ($50,000).

A new $150,000 prize will also be at stake for what HP called the "Exploit Unicorn," a multi-exploit string able to not only hack IE11 on Windows 8.1, but also obtain system-level code execution when Microsoft's Enhanced Mitigation Experience Toolkit (EMET), a utility that manually enables anti-exploit technologies such as ASLR (address space layout randomization) and DEP (data execution prevention) for specific applications, is enabled.

"We're trying to highlight the prowess of the best researchers in the world," said Brian Gorenc, manager of vulnerability research for ZDI, in an interview Friday, referring to the grand prize. "We know that researchers are looking at this [EMET], and we wanted to make this extra difficult."

To grab the $150,000, researchers will have to bypass IE11's "sandbox," a defensive technology that isolates the browser from the rest of the operating system, then leverage at least one additional vulnerability to gain system access -- all while EMET is in action.

While Gorenc acknowledged that the addition of EMET is in part an artificial hurdle designed to make exploitation more difficult, there's some method to the madness: Microsoft has increasingly pitched EMET, even to individual users, as a stop-gap defense to use between the time a new vulnerability has been discovered and when the bug is patched.

Pwn2Own, which is in its eighth year, will run March 12-13 at the CanSecWest security conference in Vancouver, British Columbia. Google will also be running its own Pwnium contest -- which will pit researchers against its Chrome OS -- at CanSecWest, and will be kicking in 25% of the prize money for Pwn2Own.

This year's Pwn2Own will again use a random drawing to choose the order that researchers tackle a target. Each researcher or team of researchers will have 30 minutes to demonstrate their exploit. If successful, the prize money will be awarded and researchers who didn't get a favorable draw will be out of luck.

"The #Pwn2own random drawing shit is back this year, a very bad rule that was removed last year where all pwners were allowed to pwn," said Chaouki Bekrar, CEO of French vulnerability research lab and zero-day seller Vupen, in a tweet yesterday.

Actually, Pwn2Own used the drawing in 2013, but during the challenge the prize pool was expanded to give every successful exploit the winning prize money, which resulted in several earning $20,000 each for hacking Java.

Gorenc said the same may happen at this year's contest, depending on how many register for the contest.

Pwn2Own has been dominated in recent years by teams to the detriment of individuals who cannot compete with groups of well-armed collectives, such as the team from Vupen, which walked off with $250,000 in prize money last year for hacking IE10, Firefox, Flash and Java.

"I'm trying to remember, who has won pwn2own by themselves besides me, @dinodaizovi, and @nils?" asked Charlie Miller, a Twitter researcher who has won four times at Pwn2Own, most recently in 2011. "The team aspect takes the fun out if it [in my opinion]."

Another individual winner, Peter Vreugdenhil, who took home $10,000 in 2010, now works for Exodus Intelligence, a firm that includes Aaron Portnoy, who once ran Pwn2Own. Several others individually won prizes last year by hacking Adobe Reader and Oracle's Java.

Gorenc disagreed with Miller, and dismissed the idea that teams, especially large ones like Vupen's, skewed the contest. "Every year, we sit down and think about how to make Pwn2Own more interesting," said Gorenc. "Last year, we thought about [individuals versus teams] but just went forward with one contest. If people want to team up and split the prize money, that's up to them."

The total payout in 2013 was a record $480,000.

Bekrar also criticized the Exploit Unicorn challenge, arguing that the $150,000 prize is inadequate when three different zero-day vulnerabilities are needed to win. "Unicorn prize is useless as it requires to burn 3 0days: IE + sandbox bypass + kernel exploit, while two would be enough," he said on Twitter.

According to Gorenc, there is no three-vulnerability minimum for the grand prize. "If they can make it happen in just two, and followed the rules, we'd be glad to give them the prize," Gorenc said.

TippingPoint and its ZDI bounty program have sponsored or co-sponsored Pwn2Own since its 2007 inception. After researchers hand over the vulnerabilities they used to hack targets -- and their exploit code -- ZDI confirms the results, then passes the information to the pertinent vendors, which often have representatives on-site, ready to jump on patching.

"For us, the contest does multiple things," said Gorenc. "We get to understand and fix exploit techniques and vulnerabilities that are out there, and we get to deploy protections to our customers. It's a good value for us."

HP has published the 2104 Pwn2Own rules on its website, and will provide updates during the contest via a Twitter account and blog.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is [email protected].

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