Opera allows remote attackers to cause a denial of service (invalid memory reference and application crash) via a web page or HTML email that contains a TBODY tag with a large COL SPAN value, as demonstrated by mangleme.

Opera 7.50 and earlier allows remote web sites to provide a "Shortcut Icon" (favicon) that is wider than expected, which could allow the web sites to spoof a trusted domain and facilitate phishing attacks using a wide icon and extra spaces.

Argument injection vulnerability in Opera before 7.50 does not properly filter "-" characters that begin a hostname in a telnet URI, which allows remote attackers to insert options to the resulting command line and overwrite arbitrary files via (1) the "-f" option on Windows XP or (2) the "-n" option on Linux.

Heap-based buffer overflow in Opera 6.05 through 7.10 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a filename with a long extension.

Cross-site scripting (XSS) vulnerability in Opera 6.0 through 7.0 with automatic redirection disabled allows remote attackers to inject arbitrary web script or HTML via the HTTP Location header.