AUSCERT External Security Bulletin Redistribution
         ESB-2000.104 -- Red Hat Security Advisory RHSA-2000:028-02
                           Netscape 4.73 available
                                 25 May 2000


	AusCERT Security Bulletin Summary

Product:		Netscape Navigator
                        Netscape Communicator
Vendor:			Red Hat
Operating System:	Red Hat Linux 6.2
                        Red Hat Linux 5.2
Platform:		x86, alpha

Impact:			Access Confidential Data
Access Required:	Remote

Ref:                    ESB-2000.095

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                   Red Hat, Inc. Security Advisory

Synopsis:          Netscape 4.73 available
Advisory ID:       RHSA-2000:028-02
Issue date:        2000-05-19
Updated on:        2000-05-19
Product:           Red Hat Linux
Keywords:          netscape SSL telnet rlogin
Cross references:  http://www.securityfocus.com/vdb/bottom.html?section=discussion&vid=1188
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1. Topic:

Netscape 4.73 packages are available. These new packages fix
bugs in SSL certificate validation; these bugs could allow
for the compromising of encrypted SSL sessions.

It is recommended that all users of Netscape update to the new packages.

2. Relevant releases/architectures:

Red Hat Linux 5.2 - i386
Red Hat Linux 6.2 - i386 alpha

3. Problem description:

The description of the vulnerability, taken from
- --
An   attacker  poisons  a  nameserver   to  redirect  all
connections to www.goodguy.com, normally,    to,    www.badguy.com.

The  attacker causes  all normal http  requests to return
what  they normally would on www.goodguy.com, even though
a   user  attempting  to   contact  www.goodguy.com  hits

Upon  getting  a  hit  to  www.badguy.com,  the  attacker
causes  an SSL connection to  be established. This can be
done  by embedding a small image. The user may or may not
get  a warning about establishing  a secure connection --
this  warning is on by  default, although many users will
choose  to disable  this warning.  The attacker  needs to
use  a legitimate SSL key, certified by someone listed as
trustworthy (thwate.com, for instance)

The  user can  continue to shop to  their hearts content,
on the real site, as it's being proxied.

When  the user decides  to check out, it  will attempt to
establish  an  SSL  connection  to www.goodguy.com.  Upon
checking   the  ip   address  for   www.goodguy.com,  for
establishing  an SSL connection, it will note that an SSL
connection  already exists to it's  IP. The key, however,
was  issued to www.badguy.com. The SSL connection will be
established,  and  by  all indications  appear  to  go to
www.goodguy.com,  when in  fact it is  to www.badguy.com.

This  could  be  used by  a  would be  attacker  to steal
information   such   as  credit   cards,  or   any  other
information protected by SSL.
- ---

Another minor vulnerability exists in current versions
of Netscape; by default, netscape will respond to
rlogin: and telnet: URLs by launching a helper application
of the appropriate type. It is possible that when following URLs
of these types that certain information about the local
user (user name, environment settings) can be exposed to
a remote host. To change the default associations to avoid
this, users can go to Edit->Preferences, and choose
Communicator->Applications. Then, change the default
commands associated with 'telnet' and 'rlogin' to something
that does not open up a connection to the remote host,
for example, simply 'xterm'.

4. Solution:

For each RPM for your particular architecture, run:

rpm -Fvh [filename]

where filename is the name of the RPM.

For Red Hat Linux 5.0 and 5.1, use the Red Hat Linux 5.2
packages. For Red Hat Linux 6.0 and 6.1, use the Red Hat Linux
6.2 packages.

5. Bug IDs fixed (http://bugzilla.redhat.com/bugzilla for more info):

11379 - Netscape 4.73 release for security problems in 4.72

6. RPMs required:

Red Hat Linux 5.2:



Red Hat Linux 6.2:




7. Verification:

MD5 sum                           Package Name
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3e881194baf12d2d7e761a63041ba404  5.2/SRPMS/netscape-4.73-0.5.2.src.rpm
52498e09827f5e854f99e320e2923fc4  5.2/i386/netscape-common-4.73-0.5.2.i386.rpm
1e15dfb4454c36e7352cd1803974f871  5.2/i386/netscape-communicator-4.73-0.5.2.i386.rpm
703a4a0b80ca0c45967cb8cc569b0600  5.2/i386/netscape-navigator-4.73-0.5.2.i386.rpm
a83932536aef2837be8733621c3415d0  6.2/SRPMS/netscape-4.73-1.src.rpm
bb79a4d70ebc7ab6cd91c04fbb951ca8  6.2/SRPMS/netscape-alpha-4.73-1.src.rpm
e800a7af7c20be924469aedb75ad807f  6.2/alpha/netscape-common-4.73-1.alpha.rpm
9502f4ec6d2c99f8f61329898f31450f  6.2/alpha/netscape-communicator-4.73-1.alpha.rpm
d812be498d83e19dba903282c8805ee2  6.2/alpha/netscape-navigator-4.73-1.alpha.rpm
de054f11902c5777446baff909da817c  6.2/i386/netscape-common-4.73-1.i386.rpm
d3825c0c61838da0b35570fb0dc7e743  6.2/i386/netscape-communicator-4.73-1.i386.rpm
aea9965093a8202196f637e8385035d9  6.2/i386/netscape-navigator-4.73-1.i386.rpm

These packages are GPG signed by Red Hat, Inc. for security.  Our key
is available at:

You can verify each package with the following command:
    rpm --checksig  <filename>

If you only wish to verify that each package has not been corrupted or
tampered with, examine only the md5sum with the following command:
    rpm --checksig --nogpg <filename>

8. References:


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