Multiple vulnerabilities have been found in Iceweasel, the Debian web browser based on Mozilla Firefox: CVE-2012-5829 Heap-based buffer overflow in the nsWindow::OnExposeEvent function could allow remote attackers to execute arbitrary code. CVE-2012-5842 Multiple unspecified vulnerabilities in the browser engine could allow remote attackers to cause a denial of service or possibly execute arbitrary code. CVE-2012-4207 The HZ-GB-2312 character-set implementation does not properly handle a ~ character in proximity to a chunk delimiter, which allows remote attackers to conduct cross-site scripting attacks via a crafted document. CVE-2012-4201 The evalInSandbox implementation uses an incorrect context during the handling of JavaScript code that sets the location.href property, which allows remote attackers to conduct cross-site scripting attacks or read arbitrary files by leveraging a sandboxed add-on. CVE-2012-4216 Use-after-free vulnerability in the gfxFont::GetFontEntry function allows remote attackers to execute arbitrary code or cause a denial of service via unspecified vectors.