Re: multiple payload handling flaws in isakmpd, again

There is one important thing I forgot to mention. In isakmpd deleting an
IPsec SA also means deleting the appropriate IPsec policy in almost any
case. Take a look at pf_key_v2_delete_spi() in pf_key_v2.c. It calls
pf_key_v2_disable_sa(), the policy eraser ;-), if the SA was not
acquired through the kernel:

  if (!(sa->flags & SA_FLAG_REPLACED)
      && !(sa->flags & SA_FLAG_ONDEMAND))
    pf_key_v2_disable_sa (sa, incoming);

Now imagine an IPsec tunnel between two security gateways running
isakmpd. Both gateways are attacked, IPsec SAs and policies get removed,
...

Thomas Walpuski
Received on Jan 01 2004