Secunia Security Advisory - A security issue has been reported in Windows XP SP2, which erroneously causes the firewall to allow connections from the Internet. The problem is caused by the way certain dialers configure the routing table and how local subnets are interpreted when the 'My network (subnet) only' option is used in the Microsoft Windows Firewall. This issue only affects Windows XP with Service Pack 2 in combination with a dial-up network connection.
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