Re: [Idr] Review of draft-ietf-idr-error-handling-18

[Jeffrey Haas <[e-mail]>]

Alvaro,

On Mon, Mar 09, 2015 at 05:45:13PM +0000, Alvaro Retana (aretana) wrote:
>   5.  Security Considerations (Section 10).  It is true that malformed optional transitive attributes should not cause remote session resets.  Are remote withdrawals a new threat?  Following the logic in the introduction, an update with a malformed optional transitive attribute may not be properly checked for several hops..but once the error is detected then the NLRI may use Treat-as-withdraw..  Assuming an AS-level granularity in checking, this won?t cause loops or major disruptions, but nonetheless it can result in not everyone receiving the information it should..

I'm not sure one can really stretch this point to be an attack vector.
Normal BGP operational policy permits an operator to advertise or not a
given prefix.  If an upstream injects malformed information and some subset
of routers are capable of announcing it and others are not the issue remains
that the upstream reachability is invalid.  

-- Jeff