Opera for Windows v7.x prior to v7.23 build 3227 contains a file overwrite vulnerability which allows remote downloads to overwrite any file on the filesystem.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/32349/opera-7.overwrite.txt
Source: https://packetstormsecurity.com/files/32349/opera-7.overwrite.txt.html