The remote host is missing a critical security patch or upgrade.
The remote host is using Mozilla. The installed version of Mozilla contains various security issues, several of which are critical as they can be easily exploited to execute arbitrary shell code on the remote host. The version of Mozilla is vulnerable to multiple denial of service attacks, overflows, information disclosure, privilege escalation, and other issues. An attacker exploiting these flaws would need to be able to convince a Mozilla user to browse to a malicious URI.
Upgrade to version 1.7.13 or higher.