In what must be a big surprise to everyone (not), another big flaw in IE has been found that effects even XP SP2 systems that can have you infected just by looking at a malicious web site. Secunia have upgraded its advisory to “extremely critical”, which is their strongest warning.
Read more about this nasty flaw at Techworld.
Also recently discovered are a couple of security flaws for older versions of Firefox, Mozilla and Thunderbird, so if your not running the most recent releases, you should update. The current versions of all apps are apparently unaffected by the flaws.