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CA-2003-21 GNU Project FTP Server Compromise


CERT Advisory CA-2003-21 GNU Project FTP Server Compromise

Original issue date: August 13, 2003
Last revised: --
Source: CERT/CC

A complete revision history is at the end of this file.


The CERT/CC has received a report that the system housing the primary
FTP servers for the GNU software project was compromised.

I. Description

The GNU Project, principally sponsored by the Free Software Foundation
(FSF), produces a variety of freely available software. The CERT/CC
has learned that the system housing the primary FTP servers for the
GNU software project,, was root compromised by an
intruder. The more common host names of and
are aliases for the same compromised system. The compromise is
reported to have occurred in March of 2003.

The FSF has released an announcement describing the incident.

Because this system serves as a centralized archive of popular
software, the insertion of malicious code into the distributed
software is a serious threat. As the above announcement indicates,
however, no source code distributions are believed to have been
maliciously modified at this time.

II. Impact

The potential exists for an intruder to have inserted back doors,
Trojan horses, or other malicious code into the source code
distributions of software housed on the compromised system.

III. Solution

We encourage sites using the GNU software obtained from the
compromised system to verify the integrity of their distribution.

Sites that mirror the source code are encouraged to verify the
integrity of their sources. We also encourage users to inspect any and
all other software that may have been downloaded from the compromised
site. Note that it is not always sufficient to rely on the timestamps
or file sizes when trying to determine whether or not a copy of the
file has been modified.

Verifying checksums

The FSF has produced PGP-signed lists of known-good MD5 hashes of the
software packages housed on the compromised server. These lists can be
found at

Note that both of these files and the announcement above are signed by
Bradley Kuhn, Executive Director of the FSF, with the following PGP

pub 1024D/DB41B387 1999-12-09 Bradley M. Kuhn <>
Key fingerprint = 4F40 645E 46BE 0131 48F9 92F6 E775 E324 DB41 B387
uid Bradley M. Kuhn (bkuhn99) <>
uid Bradley M. Kuhn <>
sub 2048g/75CA9CB3 1999-12-09

The CERT/CC believes this key to be valid.

As a matter of good security practice, the CERT/CC encourages users to
verify, whenever possible, the integrity of downloaded software. For
more information, see IN-2001-06.

Appendix A. - Vendor Information

This appendix contains information provided by vendors for this
advisory. As vendors report new information to the CERT/CC, we will
update this section and note the changes in our revision history. If a
particular vendor is not listed below, we have not received their

Free Software Foundation

The current files on and as of 2003-08-02 have
all been verified, and their md5sums and the reasons we believe the
md5sums can be trusted are in:

We are updating that file and the site as we confirm good md5sums of
additional files. It is theoretically possible that downloads between
March 2003 and July 2003 might have been source-compromised, so we
encourage everyone to re-download sources and compare with the current
copies for files on the site.

Appendix B. References

* FSF announcement regarding the incident -
* CERT Incident Note IN-2001-06 -

The CERT/CC thanks Bradley Kuhn and Brett Smith of the Free Software
Foundation for their timely assistance in this matter.

Feedback can be directed to the author: Chad Dougherty.

This document is available from:

CERT/CC Contact Information

Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:
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Software Engineering Institute
Carnegie Mellon University
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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
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Conditions for use, disclaimers, and sponsorship information

Copyright 2002 Carnegie Mellon University.

Revision History
August 13, 2003: Initial release

Version: PGP 6.5.8


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