Google has patched 14 vulnerabilities in Chrome and handed out a record $47,500 in rewards to researchers, including $30,000 for "sustained, extraordinary" contributions to its bug-reporting programme.
The record checks were cut just a few days before Google will put up to $1 million on the line at CanSecWest, a security conference which will run until March 8.
The security update to Chrome 17 was the second for that version since it launched on February 8 .
All 14 of the vulnerabilities patched yesterday were labelled "high", Google's second-most-serious threat ranking.
Ten of the bugs were tagged as "use-after-free" memory management vulnerabilities, a common type of bug reported by researchers, who continue to use Google's own memory error detection tool, AddressSanitizer, to sniff out flaws.
While the 14 bugs reported by four outside researchers earned them $17,500 in bounty payments, Google also rewarded three of them with surprise bonuses of $10,000 each for what it said was "sustained, extraordinary" work.
$73,000 in bounties this year
The three bonuses went to researchers Aki Helin and Arthur Gerkis, and to someone identified as "miaubiz." All three reported vulnerabilities that Google patched on March 4.
They also have been among the most prolific researchers for Google.
In 2011, for example, miaubiz earned more than $40,000 in bounties, while Helin took home $7,500 and Gerkis received $4,000.
"To determine the $10,000 rewards, we looked at bug finding performance over the past few months," said Jason Kersey, a Chrome program manager. "We have always reserved the right to arbitrarily reward sustained, extraordinary contributions. We reserve the right to do so again and reserve the right to do so on a more regular basis!"
So far this year, Google has paid nearly $73,000 to outside researchers.
It could lay out a lot more than that this week at CanSecWest, the Vancouver, British Columbia, security conference that opens today.
Adobe Flash upgrade
Last week, Google withdrew its sponsorship of the annual Pwn2Own hacking contest at CanSecWest, and instead said it would offer up to $1 million in cash prizes to researchers who demonstrate exploits of unknown Chrome vulnerabilities.
Google will pay $60,000 for what it called a "full Chrome exploit" - one that successfully hacks Chrome on Windows 7 using only vulnerabilities in Chrome itself - $40,000 for every partial exploit that uses one bug within Chrome and one or more in other software, and $20,000 for "consolation" exploits that hack Chrome without using any vulnerabilities in the browser.
The company has promised to pay out as much as $1 million, assuming it has that many takers.
Also included with Sunday's Chrome 17 was an update to Adobe Flash Player. Google again beat Adobe to the punch on delivering a Flash upgrade; Adobe issued a security update that fixes two critical flaws in the popular media software.
Adobe credited two members of Google's security team, Tavis Ormandy and Fermin Serna, with reporting the Flash bugs.
Sunday's update to Chrome 17 can be downloaded for Windows, Mac OS X and Linux from Google's website. Users running the browser will be updated automatically through its silent service.