[CORE SDI ADVISORY] Netscape servers Denial of Service

[Iván Arce <core.lists.bugtraq () CORE-SDI COM>]

                                                     CORE SDI
                                          http://www.core-sdi.com
                   Vulnerability Report For Netscape servers  Denial of
Service

Date Published: 2000-10-31

Advisory ID: CORE-2000103102

Bugtraq ID: 1867

CVE CAN: Non currently assigned.

Title: Netscape servers Denial of Service

Class: Denial of Service

Remotely Exploitable: Yes

Locally Exploitable: Yes

Release Mode: USER RELEASE

  Communications with the vendor have been remarkably difficult
  and to a large degree unproductive. Our last point of contact
  was October 18, 2000. This last communication stated that
  they would getting back to us shortly.
  Twelve days and several emails later we have decided to
  release without vendor support as it seems unlikely to be
  forthcoming.

Vulnerability Description:

  A bug in several components of the Netscape Servers suite of
  products allows and attacker to successfully conduct a denial
  of service attack against the vulnerable systems.
  The Netscape Certificate Management System has also several server
  components that share the problem.

Vulnerable Packages/Systems:

  Netscape Certificate Management System 4.2 (Microsoft Windows NT 4.0
version)
  Netscape Directory Server 4.12 (Microsoft NT 4.0 version)

Solution/Vendor Information/Workaround:

  Contact the vendor for a fix. Patches for iPlanet products are
  usually available from:

  Additionally, advisories and information on security issues
  of these particular Netscape products can be obtained from:

  iPlanet Certificate Management System
    http://www.securityfocus.com/bid/1839
    http://www.securityfocus.com/bid/676

  Netscape Directory Server
   http://www.securityfocus.com/bid/1839
   http://www.securityfocus.com/bid/676

Vendor notified on: October 2nd, 2000

  Last contact with the vendor was on October 18th, 2000
  when CORE SDI was informed that a patch for a problem
  reported previously was available and that information
  and a status report for the vulnerability described
  in this advisory would be available later that day.
  Since then no communication from the vendor was
  received, even after two emails asking for
  an update on October 23rd. and October 30th.

Credits:

  This vulnerability was found by Emiliano Kargieman and
  Agustin Kato Azubel from Core SDI S.A.

  This advisory was drafted with the help of the SecurityFocus.com
  Vulnerability Help Team. For more information or assistance
  drafting advisories please mail vulnhelp () securityfocus com.

Technical Description - Exploit/Concept Code:

  The Netscape Directory Server 4.12 provides a Web to LDAP gateway,
   by means of the Directory Services Gateway (DSGW) web server.
  No authentication credentials are required from the client to access DSGW.
  The same service is installed and used as part of the Certificate
Management
  System (Netscape/iPlanet CMS 4.2) and in this case it listens on a tcp
  port chosen during the installation process (24326/tcp in this example).

  A request with an URI as follows:
   http://server:24326/dsgw/bin/search?context=%

  will trigger an exception at 0x00403c62 and cause the server to hang
  and stop servicing requests until the exception generated is dismissed.
  The same problem is present in all the binaries in the
  Netscape\Server4\dsgw\bin directory (auth,csearch,dnedit,doauth,
  domodify,dosearch,edit,lang,newentry,search,unauth), except for the
  program 'tutor'.

  The '%' can be replaced by any string with a non-alphanumeric character
  in it, except for '_' and '-'. The string length doesn't matter in
  this specific problem, as shown in the example above, a string
  of just one non-alphanumeric character is enough.

  The problem lies in a function that uses a buffer that is allocated
  if the string after 'context=' is alphanumeric, but isn't if the string
  is non-alphanumeric.

DISCLAIMER:
  The contents of this advisory are copyright (c) 2000 CORE SDI S.A.
  and may be distributed freely provided that no fee is charged for this
  distribution and proper credit is given.

$Id: Netscape-Servers-DoS-advisory.txt,v 1.4 2000/10/31 22:51:27 iarce Exp $
---

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 a house from a horse by the roof on the house,
 It's nature and laws have been exhaustively expounded by Locke,
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Iván Arce
Presidente
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email   : iarce () core-sdi com
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