Integer overflow in the JavaScript engine in Avant Browser 11.7 Build 9 and earlier allows remote attackers to cause a denial of service (application crash) by attempting to URL encode a string containing many instances of an invalid character.

Argument injection vulnerability in Avant Browser 10.1 Build 17 allows user-assisted remote attackers to modify command line arguments to an invoked mail client via " (double quote) characters in a mailto: scheme handler, as demonstrated by launching Microsoft Outlook with an arbitrary filename as an attachment. NOTE: it is not clear whether this issue is implementation-specific or a problem in the Microsoft API.