Following the Mozilla Foundation’s Firefox update earlier this week, which fixed a total of 8 security issues, Opera has also released a security update addressing six security problems found in its browser.

A 'highly critical' vulnerability found version 9.21 of Opera, caused by the browser's misuse of application memory when removing BitTorrent transfers from the transfer list, can be exploited by malicious users to execute arbitrary code to remotely compromise a user's system.

The vulnerability is detailed in an advisory published by iDefense, a subsidiary of Internet and security services provider VeriSign. The problem, plus five other security issues, can be fixed by upgrading to Opera 9.22.