In the last-minute Chrome fixes before the hacking contest Pwn2Own, Google on Tuesday addressed a total of 25 vulnerabilities.

Out of the total 25 vulnerabilities, 15 were rated “high,” three were labeled "medium"; and the remaining 7 were rated as only "low." None of the vulnerabilities was labeled “critical”.

Google distributed $16,174 in bounties for finding & reporting 15 of the vulnerabilities fixed in the most recent patches. Researchers Sergey Glazunov and Daniel Divricean pocketed $6,500 and $3,174 respectively. So far in 2011, Google has already paid out around $50,000 in bug bounties.

The Pwn2Own hacking contest will launch on Wednesday, March 9, and run through Friday, March 11, at the CanSecWest security conference in Vancouver, Canada.

During the contest, hackers will try to take down the latest versions of Web browsers, including Microsoft’s Internet Explorer 8, Mozilla’s Firefox 3.6, Apple’s Safari 5 and Google’s Chrome 9.

The first hacker to take down Chrome on Wednesday will receive $20,000 from Google. If no one takes down the browser on Wednesday, Google will give only $10,000 for a successful hack on Thursday or Friday.