Avant Browser 11.7 Builds 35 and 36 allows remote attackers to spoof the address bar, via window.open with a relative URI, to show an arbitrary URL on the web site visited by the victim, as demonstrated by a visit to an attacker-controlled web page, which triggers a spoofed login form for the site containing that page. NOTE: a related attack was reported in which an arbitrary file: URL is shown.

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.

Stack-based buffer overflow in Avant Browser 11.0 build 26 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long Content-Type HTTP header.

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.

Buffer overflow in Avant Browser 8.02 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long URL in an HTTP request.