DST2K0003 : Buffer Overrun in NAI WebShield SMTP v4.5.44 Managem ent Tool

[securityteam () DELPHISPLC COM (Security Team)]

> ==========================================================================
> ======
>                                Delphis Consulting Plc
> ==========================================================================
> ======
>
>                                      Security Team Advisories
>                                   [08/05/2000]
>
>
>                            securityteam () delphisplc com
>       
> ==========================================================================
> ======
> Adv   :       DST2K0003
> Title :       Buffer Overrun in NAI WebShield SMTP v4.5.44 Management Tool
> Author        :       DCIST (securityteam () delphisplc com)
> O/S   :       Microsoft Windows NT v4.0 Server (SP6)
> Product       :       NAI WebShield SMTP v4.5.44
> Date  :       08/05/2000
>
> I. Description
>
> II. Solution
>
> III. Disclaimer
> ==========================================================================
> ======
>
>
> I. Description
> ==========================================================================
> ======
>
> Delphis Consulting Internet Security Team (DCIST) discovered the following
> vuln-
> erability in the NAI Management Agent for WebShield SMTP under Windows NT.
>
> Firstly telneting to a machine which runs the management agent on port
> 9999 will
> allow you to gain the current configuration by executing the command
> below.
>
> GET_CONFIG<CR>
>
> Secondly if you pass an oversized buffer of 208 bytes or more within one
> of the
> configuration parameters (there may be more) the service will crash
> overwriting
> the stack but and the EIP (208 + 4) with what ever was passed within the
> parameter.
>
> SET_CONFIG<CR>
> Quarantine_Path='Ax208'+ EIP
>
> This enables an attack to execute arbitrary code on host server inheriting
> the
> permissions of account of which the service was running as.
>
>
> II. Solution
> ==========================================================================
> ======
>
> Vendor Contacted: 8-May-2000
>
> Currently there is no vendor patch available but the following are
> preventative
> measures Delphis Consulting Internet Security Team would advise users
> running
> this service to implement the following.
>
> o Don't allow the service to run as SYSTEM but as a restricted user
> account.
> o Access list port 9999 on the local router or firewall to restrict access
> to only required machines.
> o Stop the management service.
>
>
> III. Disclaimer
> ==========================================================================
> ======
> THE INFORMATION CONTAINED IN THIS ADVISORY IS BELIEVED TO BE ACCURATE AT
> THE TIME OF PRINTING, BUT NO REPRESENTATION OR WARRANTY IS GIVEN, EXPRESS
> OR
> IMPLIED, AS TO ITS ACCURACY OR COMPLETENESS.  NEITHER THE AUTHOR NOR THE
> PUBLISHER ACCEPTS ANY LIABILITY WHATSOEVER FOR ANY DIRECT, INDIRECT OR
> CONSEQUENTIAL LOSS OR DAMAGE ARISING IN ANY WAY FROM ANY USE OF, OR
> RELIANCE
> PLACED ON, THIS INFORMATION FOR ANY PURPOSE.
> ==========================================================================
> ======