eTeknix reports Opera Software disclosed that it suffered from a hack attack on June 19th. No user data got stolen but at least one old and expired Opera code signing certificate got stolen, which has allowed the hackers to distribute malware to Opera browser users:
“This has allowed them to distribute malicious software which incorrectly appears to have been published by Opera Software, or appears to be the Opera browser” said Opera’s Sigbjørn Vik
Apparently Opera are working hard to try and fix the problem by introducing a new version of the Opera browser that uses a new code signing certificate. Any users who used Opera between 1:00 and 1:36 UTC on the day of the breach (June 19th) could have had malicious software installed onto their computer automatically without their knowing.