"We have no demonstration that this particular crash is exploitable but are issuing this advisory because some crashes of this type have been shown to be exploitable in the past," the advisory read.
The open source browser is now on version 220.127.116.11.
The Firefox update can be downloaded from the Mozilla site in versions for Windows, Mac OS X and Linux. Users running Firefox can call up the browser's built in updater, or wait for the automatic update notification, which typically appears within 24 to 48 hours after Mozilla posts a new version.
Thunderbird has not been updated since early February.