Google on Monday patched 11 vulnerabilities in Chrome, including one of the rare bugs the company has deemed critical in its browser.
It was the second time this month that Google updated Chrome to fix flaws.
One of the 11 bugs was rated "critical," Google's highest threat ranking, nine were tagged as "high" and another was labeled "medium." The critical vulnerability was the sixth with that ranking Google has patched so far this year.
Google identified that bug as one involving "memory corruption in vertex handing," referring to code that adds special effects such as textures to 3-D shapes. The company credited Michael Braithwaite, a senior software engineer with Turbulenz Limited, a U.K. online gaming platform developer, with reporting the vulnerability.
Braithwaite's bug affected only the Windows version of Chrome.
Also in Monday's collection were four vulnerabilities identified as "use-after-free" bugs, a type of memory management flaw that can be exploited to inject attack code.
As it always does, Google locked down the Chrome bug-tracking database to prevent outsiders from obtaining details on the 11 flaws. The company bars the public from the database to give users time to update, sometimes waiting months before lifting the embargo.
Google paid $8,337 in bounties to seven researchers who reported eight of the vulnerabilities patched Monday, including $1,337 to Braithwaite for the critical bug and $2,500 to frequent contributor, Sergey Glazunov, for two vulnerabilities rated high.
Yesterday's bounty total was less than half the record $17,000 that Google paid out earlier this month. So far in 2011, Google has paid out just over $120,000 to outside researchers.
Of the other three vulnerabilities, two were credited to a member of the Chrome security team -- unlike many companies, including Adobe and Microsoft , Google publicly identifies flaws its own researchers find -- and another was reported through the Zero Day Initiative (ZDI), a bounty program run by HP TippingPoint.
Neither Google or Mozilla -- the other browser maker that rewards researchers -- pay a bounty for bugs submitted via a broker like ZDI.
The just-patched Chrome can be downloaded for Windows, Mac OS X and Linux from Google's Web site. Users already running the browser will be updated automatically.