Buffer Overrun Vulnerabilities in Kerberos
Buffer Overrun Vulnerabilities in Kerberos
Privacy and Legal Notice
CIAC K-043b: Buffer Overrun Vulnerabilities in Kerberos
May 30, 2000 22:00 GMT
[Revision A 5/25/2000 Added Red Hat Linux RHSA-2000:025-08]
[Revision B 5/30/2000 Added FreeBSD FreeBSD-SA-00:20]
PROBLEM: Security vulnerabilities were found in the krb_rd_req()
function, the Kerberized Berkeley remote shell daemon (krshd),
and the v4rcp and ksu programs.
PLATFORM: Those running any of the following:
(1) Systems running services authenticated via Kerberos 4.
(2) Some systems running services authenticated via Kerberos 5.
(3) Systems running the Kerberized remote shell daemon (krshd).
(4) Systems with the Kerberos 5 ksu utility installed.
(5) Systems with the Kerberos 5 v4rcp utility installed.
DAMAGE: These vulnerabilities may allow users to gain root access.
SOLUTION: Apply the patches as directed by the advisory.
VULNERABILITY The risk is HIGH. There is at least one known exploit that will
ASSESSMENT: lead to a root compromise. These vulnerabilities have been
discussed in public forums.
[ Start of CERT Advisory ]
CERT Advisory CA-2000-06 Multiple Buffer Overflows in Kerberos
Authenticated Services
Original release date: May 17, 2000
Last revised: --
Source: The MIT Kerberos Team, CERT/CC
A complete revision history is at the end of this file.
Systems Affected
* Systems running services authenticated via Kerberos 4
* Some systems running services authenticated via Kerberos 5
* Systems running the Kerberized remote shell daemon (krshd)
* Systems with the Kerberos 5 ksu utility installed
* Systems with the Kerberos 5 v4rcp utility installed
Overview
The CERT Coordination Center has recently been notified of several
buffer overflow vulnerabilities in the Kerberos authentication
software. The most severe vulnerability allows remote intruders to
gain root privileges on systems running services using Kerberos
authentication. If vulnerable services are enabled on the Key
Distribution Center (KDC) system, the entire Kerberos domain may be
compromised.
I. Description
There are at least four distinct vulnerabilities in various versions
and implementations of the Kerberos software. All of these
vulnerabilities may be exploited to obtain root privileges.
Buffer overflow in krb_rd_req() library function
This vulnerability is present in version 4 of Kerberos. It is also
present in version 5 (in the version 4 compatibility code). This
vulnerability can be exploited in services using version 4 or 5 when
they perform version 4 authentication. This vulnerability may also be
exploited locally via the v4rcp setuid root program of Kerberos 5.
This vulnerability may be exploitable in version 4. This vulnerability
is exploitable in version 5 in conjunction with the
krb425_conv_principal() vulnerability, described below.
Buffer overflow in krb425_conv_principal() library function
This vulnerability is present in version 5's backward compatibility
code. This vulnerability is known to be exploitable in version 5 in
conjunction with an exploit of the krb_rd_req() vulnerability.
Buffer overflow in krshd
This vulnerability is only present in version 5. This vulnerability is
not related to the previous two vulnerabilities.
Buffer overflow in ksu
This vulnerability is only present in version 5, and is corrected in
krb5-1.1.1 and krb5-1.0.7-beta1. The ksu vulnerability is unrelated to
the other vulnerabilities.
The MIT Kerberos Team Advisory
The MIT Kerberos Team described these vulnerabilities in detail in an
advisory they recently issued. The text of this advisory is included
below.
|
SUMMARY
Serious buffer overrun vulnerabilities exist in many implementations
of Kerberos 4, including implementations included for backwards
compatibility in Kerberos 5 implementations. Other less serious buffer
overrun vulnerabilities have also been discovered. ALL KNOWN KERBEROS
4 IMPLEMENTATIONS derived from MIT sources are believed to be
vulnerable.
IMPACT
* 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.
DETAILS
The MIT Kerberos Team has been made aware of a security vulnerability
in the Kerberos 4 compatibility code contained within the MIT Kerberos
5 source distributions. This vulnerability consists of a buffer
overrun in the krb_rd_req() function, which is used by essentially all
Kerberos-authenticated services that use Kerberos 4 for
authentication. It is possible for an attacker to gain root access
over the network by exploiting this vulnerability.
An exploit is known to exist for the Kerberized Berkeley remote shell
daemon (krshd) for at least the i386-Linux platform, and possibly
others. The extent of distribution of this exploit is unknown at this
time.
Other buffer overruns have been discovered as well, though with less
far-reaching impact.
The existing exploit does not directly use the buffer overrun in
krb_rd_req(); rather, it uses the buffer that was overrun by
krb_rd_req() to exploit a second overrun in krb425_conv_principal().
The krb_rd_req() code itself might not be exploitable once the overrun
in krb425_conv_principal() is repaired, though it is likely that some
other method of exploit may be found that does not require that an
overrun exist in krb425_conv_principal().
VULNERABLE DISTRIBUTIONS AND PROGRAMS
Source distributions which may contain vulnerable code include:
* MIT Kerberos 5 releases krb5-1.0.x, krb5-1.1, krb5-1.1.1
* MIT Kerberos 4 patch 10, and likely earlier releases as well
* KerbNet (Cygnus implementation of Kerberos 5)
* Cygnus Network Security (CNS -- Cygnus implementation of Kerberos
4)
Daemons or services that may call krb_rd_req() and are thus vulnerable
to remote exploit include:
krshd
klogind (if accepting Kerberos 4 authentication)
telnetd (if accepting Kerberos 4 authentication)
ftpd (if accepting Kerberos 4 authentication)
rkinitd
kpopd
In addition, it is possible that the v4rcp program, which is usually
installed setuid to root, may be exploited by a local user to gain
root access by means of exploiting the krb_rd_req vulnerability.
The ksu program in some MIT Kerberos 5 releases has a vulnerability
that may result in unauthorized local root access. This bug was fixed
in krb5-1.1.1, as well as in krb5-1.0.7-beta1. Release krb5-1.1, as
well as krb5-1.0.6 and earlier, are believed to be vulnerable.
There is an unrelated buffer overrun in the krshd that is distributed
with at least the MIT Kerberos 5 source distributions. It is not known
whether an exploit exists for this buffer overrun. It is also not
known whether this buffer overrun is actually exploitable.
WORKAROUNDS
Certain daemons that are called from inetd may be safe from
exploitation if their command line invocation is modified to exclude
the use of Kerberos 4 for authentication. Please consult the manpages
or other documentation for your Kerberos distribution in order to
determine the correct command line for disabling Kerberos 4
authentication. Daemons for which this approach may work include:
krshd (*)
klogind
telnetd
(*) The krshd program may still be vulnerable to remote attack if
Kerberos 4 authentication is disabled, due to the unrelated buffer
overrun mentioned above. It is best to disable the krshd program
completely until a patched version can be installed.
The v4rcp program should have its setuid permission removed, since it
may be possible to perform a local exploit against it.
The krb5 ksu program should have its setuid permission removed, if it
was not compiled from krb5-1.1.1, krb5-1.0.7-beta1, or later code.
Merely replacing the ksu binary with one compiled from krb5-1.1.1 or
krb5-1.0.7-beta1 should be safe, provided that it is not compiled with
shared libraries (the vulnerability is related to some library bugs).
If ksu was compiled with shared libraries, it may be best to install a
new release that has the library bug fixed.
In the MIT Kerberos 5 releases, it may not be possible to disable
Kerberos 4 authentication in the ftpd program. Note that only releases
krb5-1.1 and later will have the ability to receive Kerberos 4
authentication.
FIXES
The best course of action is to patch the code in the krb4 library, in
addition to patching the code in the krshd program. The following
patches include some less essential patches that also affect buffer
overruns in potentially vulnerable code, but for which exploits are
somewhat more difficult to construct.
Please note that there are two sets of patches in this file that apply
against identically named files in two different releases. You should
separate out the patch set that is relevant to you prior to applying
them; otherwise, you may inadvertently patch some files twice.
MIT will soon release krb5-1.2, which will have these changes
incorporated.
PATCHES AGAINST krb5-1.0.x
The following are patches against 1.0.7-beta1 (roughly). The most
critical ones are:
appl/bsd/krshd.c
lib/krb4/rd_req.c
lib/krb5/krb/conv_princ.c
The rest are not as important but you may wish to apply them anyway
out of paranoia. These patches may apply with a little bit of fuzz
against releases prior to krb5-1.0.7-beta1, but there likely have not
been significant changes in the affected code. These patches may also
apply against KerbNet. The lib/krb4/rd_req.c patch may also apply
against CNS and MIT Kerberos 4.
[Patches to correct this issue in Kerberos version 5-1.0.x were
included at this point in the MIT advisory. The CERT Coordination
Center has made these patches available at the following link:
http://www.cert.org/advisories/CA-2000-06/mit_10x_patch.txt
-- CERT/CC]
|
PATCHES AGAINST krb5-1.1.1
The following are patches against 1.1.1. The most critical ones are:
appl/bsd/krshd.c
lib/krb4/rd_req.c
lib/krb5/krb/conv_princ.c
IMPORTANT NOTE: If you are upgrading to krb5-1.1.1 (or krb5-1.1, but
we recommend krb5-1.1.1 if you are going to upgrade at all) and
compile the source tree with the --without-krb4 option, then you will
also want to install the patch to login.c that is also provided below.
The rest are not as important but you may wish to apply them anyway
out of paranoia.
[Patches to correct this issue in Kerberos version 5-1.1.1 were
included at this point in the MIT advisory. The CERT Coordination
Center has made these patches available at the following link:
http://www.cert.org/advisories/CA-2000-06/mit_111_patch.txt
-- CERT/CC]
|
ACKNOWLEDGMENTS
Thanks to Jim Paris (MIT class of 2003) for pointing out the
krb_rd_req() vulnerability.
Thanks to Nalin Dahyabhai of Redhat for pointing out some other buffer
overruns and coming up with patches.
The full text of the MIT Kerberos Team advisory is also available
from:
http://web.mit.edu/kerberos/www/advisories/krb4buf.txt
II. Impact
The most significant impact of these vulnerabilities may allow a
remote intruder to gain root access to systems running vulnerable
services, including the KDC for the domain.
Buffer overflow in krb_rd_req() library function
This vulnerability may be exploited by remote users to gain root
privileges on systems running services linked against the vulnerable
library. As MIT indicated, these services include (but may not be
limited to):
krshd
klogind (if accepting Kerberos 4 authentication)
telnetd (if accepting Kerberos 4 authentication)
ftpd (if accepting Kerberos 4 authentication)
rkinitd
kpopd
Local users can execute arbitrary code as root on systems where v4rcp
is installed setuid root.
Buffer overflow in krb425_conv_principal() library function
This vulnerability can be exploited by remote users in conjunction
with the krb_rd_req vulnerability to gain root privileges on systems
running services linked against the vulnerable library.
Buffer overflow in krshd
Remote users may be able to execute arbitrary code as root on systems
running a vulnerable version of krshd.
Buffer overflow in ksu
Local users can can gain root privileges by exploiting the buffer
overflow in ksu.
III. Solution
Apply a patch from your vendor
Appendix A contains information provided by vendors for this advisory.
We will update the appendix as we receive more information. If you do
not see your vendor's name, the CERT/CC did not hear from that vendor.
Please contact your vendor directly.
Apply the MIT patches
If you are running the Kerberos 5 distribution from MIT, and can
rebuild your binaries from source, you can apply the source code
patches from MIT to correct these problems.
If you are running Kerberos version 4, you may be able to patch your
source code based on the version 5 patch provided by MIT. Only the
patches for the krb_rd_req() vulnerability need to be applied to
version 4 to address the issues described in this advisory.
With either version, you will need to recompile the libraries and the
vulnerable programs (krshd and ksu). You will also need to recompile
any programs that have been statically linked with the vulnerable
libraries. In version 4, you should also recompile the KDC server
software.
These patches are available at:
http://www.cert.org/advisories/CA-2000-06/mit_10x_patch.txt
http://www.cert.org/advisories/CA-2000-06/mit_111_patch.txt
Disable version 4 authentication in version 5 if possible
As suggested by MIT, version 4 authentication in some daemons can be
disabled at run time by supplying command line options to these
programs when started by inetd. This approach may work for the
following daemons:
krshd
klogind
telnetd
This addresses the krb_rd_req() and krb425_conv_principal()
vulnerabilities. Note that krshd may still be vulnerable to the krshd
specific vulnerability described in this document.
Upgrade to MIT Kerberos 5 version 1.2
The vulnerabilities described in this advisory will be addressed in
Kerberos 5 version 1.2. This version will be available from the MIT
Kerberos web site:
http://web.mit.edu/kerberos/www/
Appendix A. Vendor Information
Microsoft Corporation
No Microsoft products are affected by this vulnerability.
MIT Kerberos
The MIT Kerberos Team advisory on this topic is available from:
http://web.mit.edu/kerberos/www/advisories/krb4buf.txt
NetBSD
NetBSD has two codebases for crypto software, a legacy of the US's
export laws until recently (and also some patent issues).
The crypto-intl tree intended for use by those outside the US was not
affected.
For the crypto-us tree,
* krb5 was not affected
* krb4 was affected, and has been fixed in NetBSD-current since
Jeff's announcement; this fix is making it's way into the 1.4.x
release branch. We will release an advisory and patches shortly.
In summary, users of NetBSD releases 1.4.2 and earlier or -current up
until yesterday, who have installed the crypto-us "secr" set and who
have enabled kerberos4, are vulnerable.
OpenBSD
OpenBSD uses the KTH Kerberos distribution, which has been reported to
be not vulnerable.
Washington University
We do not distribute any "default" binaries which uses Kerberos. In
order to get Kerberos support, you must rebuild the software
specifically to use Kerberos (the default build will not use
Kerberos).
We believe that the University of Washington IMAP and POP3 servers are
not vulnerable. The message from MIT specifically stated that the
problem was in the Kerberos 4 routines from MIT.
Kerberos support in these servers is based upon Kerberos 5, not
Kerberos 4. UW imapd/ipop3d only uses GSSAPI and Kerberos 5 calls;
Kerberos 4 routines are never called.
There is an unsupported, contributed code, module for Kerberos 4
available in our software, but that is client only. We are not aware
of the existence of any Kerberos 4 server code for UW imapd/ipop3d.
_________________________________________________________________
The CERT Coordination Center thanks Jeff Schiller and the MIT Kerberos
Team for notifying us about this problem and their help in developing
this advisory.
_________________________________________________________________
Cory Cohen and Jeff Havrilla were the primary authors of the CERT/CC
portions of this document.
______________________________________________________________________
This document is available from:
http://www.cert.org/advisories/CA-2000-06.html
______________________________________________________________________
CERT/CC Contact Information
Email: cert@cert.org
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:
CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
U.S.A.
CERT personnel answer the hotline 08:00-20:00 EST(GMT-5) / EDT(GMT-4)
Monday through Friday; they are on call for emergencies during other
hours, on U.S. holidays, and on weekends.
Using encryption
We strongly urge you to encrypt sensitive information sent by email.
Our public PGP key is available from
http://www.cert.org/CERT_PGP.key
If you prefer to use DES, please call the CERT hotline for more
information.
Getting security information
CERT publications and other security information are available from
our web site
http://www.cert.org/
To be added to our mailing list for advisories and bulletins, send
email to cert-advisory-request@cert.org and include SUBSCRIBE
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______________________________________________________________________
NO WARRANTY
Any material furnished by Carnegie Mellon University and the Software
Engineering Institute is furnished on an "as is" basis. Carnegie
Mellon University makes no warranties of any kind, either expressed or
implied as to any matter including, but not limited to, warranty of
fitness for a particular purpose or merchantability, exclusivity or
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does not make any warranty of any kind with respect to freedom from
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_________________________________________________________________
Conditions for use, disclaimers, and sponsorship information
Copyright 2000 Carnegie Mellon University, portions copyright MIT
University.
Revision History
May 17, 2000: Initial release
[ End of CERT Advisory ]
______________________________________________________________________________
The following advisory was taken on 25 May 2000 from the URL
http://www.redhat.com/support/errata/RHSA-2000-025.html
The URL was accessed through the Red Hat Linux Errata URL at
http://www.redhat.com/support/errata/index.html
[ Start of Red Hat Linux Advisory RHSA-2000:025-08 ]
Synopsis: Updated Kerberos 5 packages are now available for Red Hat Linux.
Advisory ID: RHSA-2000:025-08
Issue Date: 2000年05月16日
Updated on: 2000年05月18日
Product: Red Hat Linux
Keywords: N/A
Cross References: N/A
1. Topic:
Security vulnerabilities have been found in the Kerberos 5 implementation
shipped with Red Hat Linux 6.2.
2. 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 packaging error was discovered in the original set of updates. This set of
update packages includes no functional differences compared to the
previously-released set.
3. Bug IDs fixed: (see bugzilla for more information)
10653 - 'stat' unresolved on "libkrb5.so.2.2" load
11496 - security-updated krb5 packages fail dependencies
4. Relevant releases/architectures:
Red Hat Linux 6.2 - i386 alpha sparc
5. RPMs required:
Red Hat Linux 6.2:
intel:
ftp://ftp.redhat.com/6.2/i386/krb5-configs-1.1.1-16.i386.rpm
ftp://ftp.redhat.com/6.2/i386/krb5-devel-1.1.1-16.i386.rpm
ftp://ftp.redhat.com/6.2/i386/krb5-libs-1.1.1-16.i386.rpm
ftp://ftp.redhat.com/6.2/i386/krb5-server-1.1.1-16.i386.rpm
ftp://ftp.redhat.com/6.2/i386/krb5-workstation-1.1.1-16.i386.rpm
alpha:
ftp://ftp.redhat.com/6.2/alpha/krb5-configs-1.1.1-16.alpha.rpm
ftp://ftp.redhat.com/6.2/alpha/krb5-devel-1.1.1-16.alpha.rpm
ftp://ftp.redhat.com/6.2/alpha/krb5-libs-1.1.1-16.alpha.rpm
ftp://ftp.redhat.com/6.2/alpha/krb5-server-1.1.1-16.alpha.rpm
ftp://ftp.redhat.com/6.2/alpha/krb5-workstation-1.1.1-16.alpha.rpm
sparc:
ftp://ftp.redhat.com/6.2/sparc/krb5-configs-1.1.1-16.sparc.rpm
ftp://ftp.redhat.com/6.2/sparc/krb5-devel-1.1.1-16.sparc.rpm
ftp://ftp.redhat.com/6.2/sparc/krb5-libs-1.1.1-16.sparc.rpm
ftp://ftp.redhat.com/6.2/sparc/krb5-server-1.1.1-16.sparc.rpm
ftp://ftp.redhat.com/6.2/sparc/krb5-workstation-1.1.1-16.sparc.rpm
6. Solution:
For each RPM for your particular architecture, run:
rpm -Fvh [filename]
where filename is the name of the RPM.
7. Verification:
MD5 sum Package Name
- -------------------------------------------------------------------------
4baa2dd96f7657285f3c2c198e2bac40 6.2/alpha/krb5-configs-1.1.1-16.alpha.rpm
2dae166f04584a45154e87bacccd2255 6.2/alpha/krb5-devel-1.1.1-16.alpha.rpm
cb6207296553c05fd4fbb8e0708f9199 6.2/alpha/krb5-libs-1.1.1-16.alpha.rpm
89e3ef03e4d067a807b057ac0c2fd2e6 6.2/alpha/krb5-server-1.1.1-16.alpha.rpm
8f54621b1eabfcb3e440858063947c29
6.2/alpha/krb5-workstation-1.1.1-16.alpha.rpm
fa04878ec530e0e8b42741bf74fbbb9d 6.2/i386/krb5-configs-1.1.1-16.i386.rpm
3f51c3141a4fcbdc03fc865f0e111c29 6.2/i386/krb5-devel-1.1.1-16.i386.rpm
c2f40d1858d8e13f825cea0b8228e89e 6.2/i386/krb5-libs-1.1.1-16.i386.rpm
cb794eb8477b9bebc0feb5030e6754c5 6.2/i386/krb5-server-1.1.1-16.i386.rpm
aaa159ad746cac605da050b2e440840f 6.2/i386/krb5-workstation-1.1.1-16.i386.rpm
acaf9130f3d0ed56ae1c444482c9ab57 6.2/sparc/krb5-configs-1.1.1-16.sparc.rpm
4d35c4294c38c4297001f04842a1d9cf 6.2/sparc/krb5-devel-1.1.1-16.sparc.rpm
93022952876e2fb5f73248e5be739322 6.2/sparc/krb5-libs-1.1.1-16.sparc.rpm
fd8dcb69e828f8a2d63543bfaee4c945 6.2/sparc/krb5-server-1.1.1-16.sparc.rpm
98ed42725c3574d4e5b4024dd65fd8fd
6.2/sparc/krb5-workstation-1.1.1-16.sparc.rpm
These packages are GPG signed by Red Hat, Inc. for security. Our key is
available at:
http://www.redhat.com/about/contact.html
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
Note that you need RPM >= 3.0 to check GnuPG keys.
8. References:
http://www.securityfocus.com/bid/1220
Copyright ゥ 2000 Red Hat, Inc. All rights reserved.
[ End of Red Hat Linux Advisory RHSA-2000:025-08 ]
______________________________________________________________________________
[ Start of FreeBSD Advisory FreeBSD-SA-00:20]
=============================================================================
FreeBSD-SA-00:20 Security Advisory
FreeBSD, Inc.
Topic: krb5 port contains remote and local root exploits.
Category: ports
Module: krb5
Announced: 2000年05月26日
Credits: Jeffrey I. Schiller
Affects: Ports collection prior to the correction date
Corrected: 2000年05月17日
Vendor status: Patch released
FreeBSD only: NO
I. Background
MIT Kerberos 5 is an implementation of the Kerberos 5 protocol which
is available in the FreeBSD ports collection as the security/krb5
port. FreeBSD also includes separately-developed Kerberos 4 and 5
implementations from KTH, which are optionally installed as part of
the base system (KTH Heimdal, the Kerberos 5 implementation, is
currently considered "experimental" software).
II. Problem Description
The MIT Kerberos 5 port, versions 1.1.1 and earlier, contains several
remote and local buffer overflows which can lead to root compromise.
Note that the implementations of Kerberos shipped in the FreeBSD base
system are separately-developed software to MIT Kerberos and are
believed not to be vulnerable to these problems.
However, a very old release of FreeBSD dating from 1997 (FreeBSD
2.2.5) did ship with a closely MIT-derived Kerberos implementation
("eBones") and may be vulnerable to attacks of the kind described
here. Any users still using FreeBSD 2.2.5 and who have installed the
optional Kerberos distribution are urged to upgrade to 2.2.8-STABLE or
later. Note however that FreeBSD 2.x is no longer an officially
supported version, nor are security fixes always provided.
The krb5 port is not installed by default, nor is it "part of FreeBSD"
as such: it is part of the FreeBSD ports collection, which contains
nearly 3300 third-party applications in a ready-to-install format. The
ports collection shipped with FreeBSD 4.0 contains this problem since
it was discovered after the release.
FreeBSD makes no claim about the security of these third-party
applications, although an effort is underway to provide a security
audit of the most security-critical ports.
III. Impact
Local or remote users can obtain root access on the system running krb5.
If you have not chosen to install the krb5 port, then your system is
not vulnerable to this problem.
IV. Workaround
Due to the nature of the vulnerability there are several programs and
network services which are affected. If recompiling the port is not
practical, please see the MIT Kerberos advisory for suggested
workarounds (including the disabling or adjustment of services and
removal of setuid permissions on vulnerable binaries). The advisory
can be found at the following location:
http://web.mit.edu/kerberos/www/advisories/krb4buf.txt
V. Solution
1) Upgrade your entire ports collection and rebuild the krb5 port. A
package is not provided for this port for export control reasons.
2) download a new port skeleton for the krb5 port from:
http://www.freebsd.org/ports/
and use it to rebuild the port.
3) Use the portcheckout utility to automate option (3) above. The
portcheckout port is available in /usr/ports/devel/portcheckout or the
package can be obtained from:
ftp://ftp.freebsd.org/pub/FreeBSD/ports/packages/devel/portcheckout-1.0.tgz
[ End of FreeBSD Advisory FreeBSD-SA-00:20]
CIAC wishes to acknowledge the contributions of CERT, Red Hat Linux, and FreeBSD for the information contained in this bulletin.
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