FreeBSD Security Advisory FreeBSD-SA-00:70 - The firewall deny feature in ppp(8) is broken in recent releases, accidently accepting all packets. Thus, users who are using the deny_incoming functionality in the expectation that it provides a "deny by default" firewall which only allows through packets known to be part of an existing NAT session, are in fact allowing other types of unsolicited IP traffic into their internal network.
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