The JavaScript engine in Mozilla Firefox and Thunderbird 1.x before 1.5 and 1.0.x before 1.0.8, Mozilla Suite before 1.7.13, and SeaMonkey before 1.0 does not properly handle temporary variables that are not garbage collected, which might allow remote attackers to trigger operations on freed memory and cause memory corruption.

The WYSIWYG rendering engine ("rich mail" editor) in Mozilla Thunderbird 1.0.7 and earlier allows user-assisted attackers to bypass javascript security settings and obtain sensitive information or cause a crash via an e-mail containing a javascript URI in the SRC attribute of an IFRAME tag, which is executed when the user edits the e-mail.

GUI display truncation vulnerability in Mozilla Thunderbird 1.0.2, 1.0.6, and 1.0.7 allows user-assisted attackers to execute arbitrary code via an attachment with a filename containing a large number of spaces ending with a dangerous extension that is not displayed by Thunderbird, along with an inconsistent Content-Type header, which could be used to trick a user into downloading dangerous content by dragging or saving the attachment.

Mozilla Firefox 1.0.1 and possibly other versions, including Mozilla and Thunderbird, allows remote attackers to spoof the URL in the Status Bar via an A HREF tag that contains a TABLE tag that contains another A tag.

Mozilla Thunderbird 1.0 and Firefox 1.0.6 allows remote attackers to obfuscate URIs via a long URI, which causes the address bar to go blank and could facilitate phishing attacks.

Firefox before 1.0.5, Thunderbird before 1.0.5, Mozilla before 1.7.9, Netscape 8.0.2, and K-Meleon 0.9 runs XBL scripts even when Javascript has been disabled, which makes it easier for remote attackers to bypass such protection.

String handling functions in Mozilla 1.7.3, Firefox 1.0, and Thunderbird before 1.0.2, such as the nsTSubstring_CharT::Replace function, do not properly check the return values of other functions that resize the string, which allows remote attackers to cause a denial of service and possibly execute arbitrary code by forcing an out-of-memory state that causes a reallocation to fail and return a pointer to a fixed address, which leads to heap corruption.

Heap-based buffer overflow in GIF2.cpp in Firefox before 1.0.2, Mozilla before to 1.7.6, and Thunderbird before 1.0.2, and possibly other applications that use the same library, allows remote attackers to execute arbitrary code via a GIF image with a crafted Netscape extension 2 block and buffer size.

The installation confirmation dialog in Firefox before 1.0.1, Thunderbird before 1.0.1, and Mozilla before 1.7.6 allows remote attackers to use InstallTrigger to spoof the hostname of the host performing the installation via a long "user:pass" sequence in the URL, which appears before the real hostname.