The company has a lot on the line at Pwn2Own, which runs March 9-11 at the CanSecWest security conference in Vancouver, British Columbia.

The first researcher to hack Chrome on Wednesday will be . If no one breaks the browser that day, the rules change and Google will fork over $10,000 for a successful exploit on Thursday or Friday, with Pwn2Own sponsor HP TippingPoint ponying up another $10,000.

Other browsers that researchers will tackle at Pwn2Own include Apple's Safari 5, Microsoft's Internet Explorer 8 and Mozilla's Firefox 3.6.

Tuesday's 25-patch update fixed 15 vulnerabilities rated "high," the second-most-severe ranking in Google's scoring; three labeled "medium"; and seven pegged as only "low."

None of the vulnerabilities was ranked "critical," the category essentially reserved for bugs that may let an attacker escape Chrome's anti-exploit "sandbox." Google has this year.