Vulnerability Note VU#386964

OpenSSL SSLv2 client code fails to properly check for NULL

Overview

A flaw in the OpenSSL library could allow a remote attacker to cause a denial of service on an affected application.

I. Description

The OpenSSL toolkit implements the Secure Sockets Layer (SSL versions 2 and 3) and Transport Layer Security (TLS version 1) protocols as well as a general purpose cryptographic library. A missing check for NULL exists in the SSLv2 client get_server_hello() function. As a result, an affected client application using OpenSSL to create an SSLv2 connection to a malicious server could be caused to crash.

II. Impact

A remote attacker could cause an affected client application to crash, creating a denial of service.

III. Solution

Upgrade or apply a patch from the vendor

Patches have been released to address this issue. Please see the Systems Affected section of this document for more information.

Users or redistributors who compile OpenSSL from the original source code distribution are encouraged to review OpenSSL Security Advisory [28th September 2006] and upgrade to the appropriate fixed version of the software.

Systems Affected

Vendor	Status	Date Notified
3com, Inc.	Unknown	15-Sep-2006
Aladdin Knowledge Systems	Unknown	15-Sep-2006
Alcatel	Unknown	15-Sep-2006
America Online, Inc.	Unknown	15-Sep-2006
Apache-SSL	Unknown	15-Sep-2006
Apache HTTP Server Project	Unknown	15-Sep-2006
Apple Computer, Inc.	Unknown	15-Sep-2006
Aruba Networks, Inc.	Unknown	15-Sep-2006
AttachmateWRQ, Inc.	Unknown	15-Sep-2006
AT&T	Unknown	15-Sep-2006
Avaya, Inc.	Unknown	15-Sep-2006
Avici Systems, Inc.	Unknown	15-Sep-2006
Borderware Technologies	Unknown	15-Sep-2006
Certicom	Unknown	15-Sep-2006
Charlotte's Web Networks	Unknown	15-Sep-2006
Check Point Software Technologies	Unknown	15-Sep-2006
Chiaro Networks, Inc.	Unknown	15-Sep-2006
Cisco Systems, Inc.	Unknown	15-Sep-2006
Clavister	Unknown	15-Sep-2006
Command Software Systems	Unknown	15-Sep-2006
Computer Associates	Unknown	15-Sep-2006
Conectiva Inc.	Unknown	15-Sep-2006
Covalent Technologies	Unknown	15-Sep-2006
Cray Inc.	Unknown	15-Sep-2006
Cryptlib	Unknown	15-Sep-2006
Crypto++ Library	Unknown	15-Sep-2006
CyberSoft, Inc.	Unknown	15-Sep-2006
D-Link Systems, Inc.	Unknown	15-Sep-2006
Data Connection, Ltd.	Unknown	15-Sep-2006
DataFellows	Unknown	15-Sep-2006
Debian GNU/Linux	Vulnerable	2-Oct-2006
EMC, Inc. (formerly Data General Corporation)	Unknown	15-Sep-2006
Engarde Secure Linux	Unknown	15-Sep-2006
Ericsson	Unknown	15-Sep-2006
eSoft, Inc.	Unknown	15-Sep-2006
Extreme Networks	Unknown	15-Sep-2006
F-PROT by FRISK Software International	Unknown	15-Sep-2006
F-Secure Corporation	Unknown	15-Sep-2006
F5 Networks, Inc.	Vulnerable	21-Sep-2006
Fedora Project	Unknown	15-Sep-2006
Finjan Software	Unknown	15-Sep-2006
Force10 Networks, Inc.	Unknown	15-Sep-2006
Fortinet, Inc.	Unknown	15-Sep-2006
Foundry Networks, Inc.	Unknown	15-Sep-2006
FreeBSD, Inc.	Vulnerable	28-Sep-2006
Fujitsu	Not Vulnerable	29-Sep-2006
Gentoo Linux	Unknown	15-Sep-2006
GFI Software, Inc.	Unknown	15-Sep-2006
Global Technology Associates	Not Vulnerable	18-Sep-2006
Hewlett-Packard Company	Unknown	15-Sep-2006
Hitachi	Unknown	15-Sep-2006
Hyperchip	Unknown	15-Sep-2006
IAIK Java Group	Unknown	15-Sep-2006
IBM Corporation	Unknown	15-Sep-2006
IBM Corporation (zseries)	Unknown	15-Sep-2006
IBM eServer	Unknown	15-Sep-2006
Immunix Communications, Inc.	Unknown	15-Sep-2006
Ingrian Networks, Inc.	Unknown	15-Sep-2006
Intel Corporation	Unknown	15-Sep-2006
Internet Security Systems, Inc.	Unknown	15-Sep-2006
Intoto	Unknown	15-Sep-2006
IP Filter	Unknown	15-Sep-2006
Juniper Networks, Inc.	Unknown	15-Sep-2006
Linksys (A division of Cisco Systems)	Unknown	15-Sep-2006
Lotus Software	Unknown	15-Sep-2006
lsh	Unknown	15-Sep-2006
Lucent Technologies	Unknown	15-Sep-2006
Luminous Networks	Unknown	15-Sep-2006
Mandriva, Inc.	Unknown	15-Sep-2006
MessageLabs	Unknown	15-Sep-2006
Microsoft Corporation	Unknown	15-Sep-2006
Microsoft Internet Explorer	Unknown	15-Sep-2006
Mirapoint, Inc.	Unknown	15-Sep-2006
mod_ssl	Unknown	15-Sep-2006
MontaVista Software, Inc.	Unknown	15-Sep-2006
Mozilla - Network Security Services	Unknown	15-Sep-2006
Mozilla, Inc.	Unknown	15-Sep-2006
Multinet (owned Process Software Corporation)	Unknown	15-Sep-2006
Multitech, Inc.	Unknown	15-Sep-2006
MySQL AB	Unknown	15-Sep-2006
NEC Corporation	Unknown	15-Sep-2006
NetBSD	Unknown	15-Sep-2006
netfilter	Unknown	15-Sep-2006
Netscape NSS	Unknown	15-Sep-2006
Network Appliance, Inc.	Unknown	15-Sep-2006
NextHop Technologies, Inc.	Unknown	15-Sep-2006
Nokia	Unknown	15-Sep-2006
Nortel Networks, Inc.	Unknown	15-Sep-2006
Novell, Inc.	Unknown	15-Sep-2006
OpenBSD	Unknown	15-Sep-2006
OpenPKG	Vulnerable	2-Oct-2006
OpenSSL	Vulnerable	28-Sep-2006
Openwall GNU/*/Linux	Unknown	15-Sep-2006
Oracle Corporation	Vulnerable	17-Jan-2007
Proland Software, Inc.	Unknown	15-Sep-2006
QNX, Software Systems, Inc.	Unknown	15-Sep-2006
Red Hat, Inc.	Vulnerable	2-Oct-2006
Redback Networks, Inc.	Unknown	15-Sep-2006
Riverstone Networks, Inc.	Unknown	15-Sep-2006
rPath	Vulnerable	2-Oct-2006
RSA Security, Inc.	Unknown	15-Sep-2006
Secure Computing Network Security Division	Unknown	15-Sep-2006
Secureworx, Inc.	Unknown	15-Sep-2006
Sendmail Consortium	Unknown	15-Sep-2006
Sendmail, Inc.	Unknown	22-Sep-2006
Silicon Graphics, Inc.	Unknown	15-Sep-2006
Slackware Linux Inc.	Vulnerable	2-Oct-2006
Sony Corporation	Unknown	15-Sep-2006
Sophos, Inc.	Unknown	15-Sep-2006
Spyrus	Unknown	15-Sep-2006
Stonesoft	Unknown	15-Sep-2006
Stunnel	Unknown	15-Sep-2006
Sun Microsystems, Inc.	Unknown	15-Sep-2006
SUSE Linux	Vulnerable	2-Oct-2006
Symantec, Inc.	Unknown	15-Sep-2006
The SCO Group	Unknown	15-Sep-2006
Trendmicro	Unknown	15-Sep-2006
Trustix Secure Linux	Vulnerable	2-Oct-2006
Turbolinux	Unknown	15-Sep-2006
Ubuntu	Vulnerable	28-Sep-2006
Unisys	Unknown	15-Sep-2006
Watchguard Technologies, Inc.	Unknown	15-Sep-2006
Wietse Venema	Unknown	15-Sep-2006
Wind River Systems, Inc.	Unknown	15-Sep-2006
ZyXEL	Unknown	15-Sep-2006

References

http://www.openssl.org/news/secadv_20060928.txt
http://jvn.jp/cert/JVNVU%23386964/index.html
http://secunia.com/advisories/23280/
http://secunia.com/advisories/23309/
http://www.securityfocus.com/bid/20246
http://www.securityfocus.com/bid/22083

Credit

Thanks to Tavis Ormandy and Will Drewry of the Google Security Team for reporting this vulnerability.

This document was written by Chad R Dougherty.

Other Information

Date Public:	2006-09-28
Date First Published:	2006-09-28
Date Last Updated:	2007-02-08
CERT Advisory:
CVE-ID(s):	CVE-2006-4343
NVD-ID(s):	CVE-2006-4343
US-CERT Technical Alerts:
Metric:	0.32
Document Revision:	29

If you have feedback, comments, or additional information about this vulnerability, please send us email.

Produced 2006 by US-CERT, a government organization
Disclaimers and copyright information

Get Adobe Reader