Mozilla Firefox before 3.5.12 and 3.6.x before 3.6.9, Thunderbird before 3.0.7 and 3.1.x before 3.1.3, and SeaMonkey before 2.0.7 on Mac OS X allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via a crafted font in a data: URL.

intl/uconv/util/nsUnicodeDecodeHelper.cpp in Mozilla Firefox before 3.6.7 and Thunderbird before 3.1.1 inserts a U+FFFD sequence into text in certain circumstances involving undefined positions, which might make it easier for remote attackers to conduct cross-site scripting (XSS) attacks via crafted 8-bit text.

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 3.5.9 and 3.6.x before 3.6.2, Thunderbird before 3.0.4, and SeaMonkey before 2.0.4 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Use-after-free vulnerability in the nsTreeSelection implementation in Mozilla Firefox before 3.0.19 and 3.5.x before 3.5.9, Thunderbird before 3.0.4, and SeaMonkey before 2.0.4 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via unspecified vectors that trigger a call to the handler for the select event for XUL tree items.

The XMLDocument::load function in Mozilla Firefox before 3.5.9 and 3.6.x before 3.6.2, Thunderbird before 3.0.4, and SeaMonkey before 2.0.4 does not perform the expected nsIContentPolicy checks during loading of content by XML documents, which allows attackers to bypass intended access restrictions via crafted content.

Mozilla Firefox before 3.0.19, 3.5.x before 3.5.9, and 3.6.x before 3.6.2; Thunderbird before 3.0.4; and SeaMonkey before 2.0.4 do not properly manage reference counts for option elements in a XUL tree optgroup, which might allow remote attackers to execute arbitrary code via unspecified vectors that trigger access to deleted elements, related to a "dangling pointer vulnerability."

Mozilla Firefox before 3.0.19, 3.5.x before 3.5.9, and 3.6.x before 3.6.2, and SeaMonkey before 2.0.4, does not prevent applets from interpreting mouse clicks as drag-and-drop actions, which allows remote attackers to execute arbitrary JavaScript with Chrome privileges by loading a chrome: URL and then loading a javascript: URL.

Mozilla Firefox before 3.0.19, 3.5.x before 3.5.9, and 3.6.x before 3.6.2, and SeaMonkey before 2.0.4, frees the contents of the window.navigator.plugins array while a reference to an array element is still active, which allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via unspecified vectors, related to a "dangling pointer vulnerability."

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 3.0.19, 3.5.x before 3.5.9, and 3.6.x before 3.6.2; Thunderbird before 3.0.4; and SeaMonkey before 2.0.4 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Mozilla Firefox before 3.5.9 and 3.6.x before 3.6.2, and SeaMonkey before 2.0.4, executes a mail application in situations where an IMG element has a SRC attribute that is a redirect to a mailto: URL, which allows remote attackers to cause a denial of service (excessive application launches) via an HTML document with many images.