Watchguard Firebox Authentication DoS



Advisory Code:   VIGILANTE-2000005



Release Date:

August 15, 2000



Systems Affected:

Tested on the newest version of the Watchguard Firebox II (that was on the

22nd of June), but it is very likely that this bug exists in all prior

versions that include the authentication service (TCP port 4100).



THE PROBLEM

Sending a malformed URL to the authentication service running on TCP port

4100, causes it to shut down and requires a reboot of the Watchguard for it

to work again.



Vendor Status:

Vendor was informed of the problem, and have been very cooperative in

getting a patch developed for the problem. According to the vendor the

problem is not caused by a buffer overflow.



Fix (quote from the vendor):

"all current WatchGuard LiveSecurity Subscribers have been

sent the Service Pack that addresses this issue.  Copies of this

Service Pack can be downloaded from the WatchGuard LiveSecurity

Archive.  To log into the archive, go to

http://www.watchguard.com/support.  A work around that addresses the

vulnerability from the external interface is to disable Authentication

to the Firebox from the external interface.  Upstream routers can also

be used to control access to this service if access to the

Authentication applet is required from the external interface and you

do  not wish to install the patch.  For obvious reasons, these are

sub-optimal solutions."



Vendor   URL: http://www.watchguard.com

Product  URL: http://www.watchguard.com/products/fIImss.asp



Copyright VIGILANTe 2000-08-15



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