Mozilla Messaging has released emergency updates to both Thunderbird 3.0 & 3.1 on October 27th. From Mozilla Developer’s News, “These releases fixed a critical security issue that could potentially allow remote code execution. This issue does not affect email or newsgroups but could be triggered through browser-like features or add-ons.“
For more information and to download:
IMPORTANT! Support for Thunderbird 3.0 is ending soon. Upgrade to Thunderbird 3.1