Originally Published: Saturday, 20 May 2000 Author: Derrick H. Lewis
Published to: news_enhance_security/Security News Page: 1/1 - [Printable]

Red Hat, Inc. Security Advisory

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.

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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 ---------------------------------------------------------------------

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 http://www.securityfocus.com/: -- 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 www.badguy.com.

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:

intel: ftp://ftp.redhat.com/5.2/i386/netscape-common-4.73-0.5.2.i386.rpm ftp://ftp.redhat.com/5.2/i386/netscape-navigator-4.73-0.5.2.i386.rpm ftp://ftp.redhat.com/5.2/i386/netscape-communicator-4.73-0.5.2.i386.rpm

sources: ftp://ftp.redhat.com/5.2/SRPMS/netscape-4.73-0.5.2.src.rpm

Red Hat Linux 6.2:

intel: ftp://ftp.redhat.com/6.2/i386/netscape-common-4.73-1.i386.rpm ftp://ftp.redhat.com/6.2/i386/netscape-navigator-4.73-1.i386.rpm ftp://ftp.redhat.com/6.2/i386/netscape-communicator-4.73-1.i386.rpm

alpha: ftp://ftp.redhat.com/6.2/alpha/netscape-common-4.73-1.alpha.rpm ftp://ftp.redhat.com/6.2/alpha/netscape-navigator-4.73-1.alpha.rpm ftp://ftp.redhat.com/6.2/alpha/netscape-communicator-4.73-1.alpha.rpm

sources: ftp://ftp.redhat.com/6.2/SRPMS/netscape-4.73-1.src.rpm ftp://ftp.redhat.com/6.2/SRPMS/netscape-alpha-4.73-1.src.rpm

7. Verification:

MD5 sum Package Name -------------------------------------------------------------------------- 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: http://www.redhat.com/corp/contact.html

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

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

8. References:


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