Firefox version 2.0.0.7 suffers from a remote denial of service vulnerability and Zaptel version 1.4.5.1 suffers from a local buffer overflow vulnerability.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/60312/firefoxzaptel-dos.txt
Source: https://packetstormsecurity.com/files/60312/firefoxzaptel-dos.txt.html