RedHat 6.2: Kerberos 5 vulnerability
Posted by LinuxSecurity.com Team   
RedHat Linux A number of possible buffer overruns were found in libraries includedin the affected packages. A denial-of-service vulnerability was also foundin the ksu program.
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                   Red Hat, Inc. Security Advisory

Synopsis:          Updated Kerberos 5 packages are now available for Red Hat Linux.
Advisory ID:       RHSA-2000:025-12
Issue date:        2000-05-16
Updated on:        2000-06-15
Product:           Red Hat Linux
Keywords:          N/A
Cross references:  N/A
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1. Topic:

Security vulnerabilities have been found in the Kerberos 5 implementation
shipped with Red Hat Linux 6.2.

2. Relevant releases/architectures:

Red Hat Linux 6.2 - i386 alpha sparc

3. Problem description:

A number of possible buffer overruns were found in libraries included
in the affected packages.  A denial-of-service vulnerability was also found
in the ksu program.

* A remote user may gain unauthorized root access to a machine running
  services authenticated with Kerberos 4.

* A remote user may gain unauthorized root access to a machine running
  krshd, regardless of whether the program is configured to accept
  Kerberos 4 authentication.

* A local user may gain unauthorized root access by exploiting v4rcp
  or ksu.

* A remote user can cause a KDC to become unresponsive or crash by sending
  it an improperly formatted request.

* A remote user may execute certain FTP commands without authorization
  on systems using the FTP server included in the krb5-workstation
  package.

* An attacker with access to a local account may gain unauthorized
  root access on systems using the FTP server included in the
  krb5-workstation package.

4. Solution:

For each RPM for your particular architecture, run:

rpm -Fvh [filename]

where filename is the name of the RPM.

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

10653 - 'stat' unresolved on "libkrb5.so.2.2" load
11496 - security-updated krb5 packages fail dependencies


6. RPMs required:

Red Hat Linux 6.2:

intel:
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/i386/krb5-configs-1.1.1-21.i386.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/i386/krb5-devel-1.1.1-21.i386.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/i386/krb5-libs-1.1.1-21.i386.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/i386/krb5-server-1.1.1-21.i386.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/i386/krb5-workstation-1.1.1-21.i386.rpm

alpha:
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/alpha/krb5-configs-1.1.1-21.alpha.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/alpha/krb5-devel-1.1.1-21.alpha.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/alpha/krb5-libs-1.1.1-21.alpha.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/alpha/krb5-server-1.1.1-21.alpha.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/alpha/krb5-workstation-1.1.1-21.alpha.rpm

sparc:
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/sparc/krb5-configs-1.1.1-21.sparc.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/sparc/krb5-devel-1.1.1-21.sparc.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/sparc/krb5-libs-1.1.1-21.sparc.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/sparc/krb5-server-1.1.1-21.sparc.rpm
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/sparc/krb5-workstation-1.1.1-21.sparc.rpm

sources:
ftp://ftp.Red Hat.com/Red Hat/updates/6.2/SRPMS/krb5-1.1.1-21.src.rpm

7. Verification:

MD5 sum                           Package Name
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220dd8648e6560215475f29f12cf7fbf  6.2/SRPMS/krb5-1.1.1-21.src.rpm
506aa4887dbb63ee0fdf1b0617db5d92  6.2/alpha/krb5-configs-1.1.1-21.alpha.rpm
19d3648a64b259a3a83ef70ecf3c1d3e  6.2/alpha/krb5-devel-1.1.1-21.alpha.rpm
ea30e1a247aa7d4c516ead13c825c8cb  6.2/alpha/krb5-libs-1.1.1-21.alpha.rpm
55805f5199f7c2c24c03f4609a2cbd81  6.2/alpha/krb5-server-1.1.1-21.alpha.rpm
a98473df43eedf564efe9a05b30c2baf  6.2/alpha/krb5-workstation-1.1.1-21.alpha.rpm
43d0af74bb628d446dc8781e9d0ae08b  6.2/i386/krb5-configs-1.1.1-21.i386.rpm
d13ac3cc0e680b0e452aeb34749ea7b4  6.2/i386/krb5-devel-1.1.1-21.i386.rpm
76882356337e55cd3bd5e0d5cfa454de  6.2/i386/krb5-libs-1.1.1-21.i386.rpm
93efde6cc79b16245f5e27e793a8a4ad  6.2/i386/krb5-server-1.1.1-21.i386.rpm
aa00aa8b26a50b75317f51e447a17420  6.2/i386/krb5-workstation-1.1.1-21.i386.rpm
ff7f959f22e80e9aeabb3a1c6602e225  6.2/sparc/krb5-configs-1.1.1-21.sparc.rpm
1cce9df9c5591fe43c1340334d01d6be  6.2/sparc/krb5-devel-1.1.1-21.sparc.rpm
cc67fdfad917452f383e45a9945e5ae0  6.2/sparc/krb5-libs-1.1.1-21.sparc.rpm
0215d914b0d9e2f78830ef7df9b14fea  6.2/sparc/krb5-server-1.1.1-21.sparc.rpm
3f564e722e61c1e4e8bd1a3faa108b3d  6.2/sparc/krb5-workstation-1.1.1-21.sparc.rpm

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

http://www.securityfocus.com/bid/1220
http://www.securityfocus.com/bid/1338
http://web.mit.edu/kerberos/www/advisories/index.html

Thanks to Chris Evans, Mike Friedman, Jim Paris, Matt Power, Andrew
Newman, Christopher R. Thompson, and Marcus Watts for reporting these
problems to us and the Kerberos 5 team.