RE: Why TCP is more secure than UDP?

["David Gillett" <gillettdavid () fhda edu>]

  In order to spoof a UDP packet, *all* you need to do is spoof the
source IP address.
  To successfully spoof a TCP packet, you need to also successfully spoof
TCP header fields relating to the state of the connection, such as the
sequence number.  Rather difficult to do reliably unless you've also been 
sniffing the conversation. 

  It would be possible to build a UDP-based application protocol that 
tracked state and sequence number, and so was "as secure as TCP".  In
the process, you would probably lose all of UDP's performance advantage,
and your implementation would likely still be a little weaker than what
is already built into TCP.

David Gillett


> -----Original Message-----
> From: listbounce () securityfocus com 
> [mailto:listbounce () securityfocus com] On Behalf Of pal_adam () gmx net
> Sent: Tuesday, July 10, 2007 1:37 AM
> To: security-basics () securityfocus com
> Cc: paavan.shah () gmail com
> Subject: Re: Why TCP is more secure than UDP?
>
> Hi 
>
> I dont understand what you mean by spoofing, since wherever 
> you use UDP or TCP the underlying layer still remains IP so 
> when you spoof a source you spoof an IP source.
> If you talk about a man-in-the-middle attack then taking a 
> closer look at both protocols will show that UDP doesnt 
> establish any connection before starting the communication.
> Using TCP you`ll need to ACK incomming data using a 
> pre-established sequence number which makes the attack on TCP 
> harder but not impossible.
>
>
> regards 
>
> Adam Pal
>
>
>
> -------- Original-Nachricht --------
> Datum: 10 Jul 2007 02:11:12 -0000
> Von: paavan.shah () gmail com
> An: security-basics () securityfocus com
> Betreff: Why TCP is more secure than UDP?
>
> > It is said that UDP is considered more vulnerable to 
> spoofing than TCP?
> > Can anyone point me to any document/link which describes 
> TCP is more 
> > secure than UDP
>
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