This is a big deal. While Cisco is the number one router and gateway vendor, Juniper is not small by any means – and with the properly crafted traffic, a Juniper gateway can be crashed. This then affects any traffic that will use that gateway, no matter where it is going.
Releases 3 through 10 of Junos are vulnerable; there is no way to fix this problem with the firewall or other work arounds. Releases that were released later than January 8, 2009, are not vulnerable.