Warning on "Exploit.CodeBaseExec" means that HTML page being scanned contains code exploiting the Microsoft Internet Explorer Arbitrary Program Execution Vulnerability, aka the Local Executable Invocation via Object tag vulnerability.
Many suspicious websites use this vulnerability to try do gain access to the local computer.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.
Microsoft Internet Explorer 5.01, 5.5 and 6.0 treat objects invoked on an HTML page with the codebase property as part of the Local Computer zone, which allows remote attacks to invoke executables present on the local system through objects such as the popup object.
More information on this vulnerability can be found from: https://www.microsoft.com/technet/security/bulletin/ms02-015.asp?frame=true#CV...
Microsoft released a patch on March 28, 2002 that eliminates this vulnerability in Internet Explorer. To download this patch go to the following link: https://www.microsoft.com/windows/ie/downloads/critical/Q319182/default.asp