CVE Name:       CAN-2005-0753

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including descriptions of the fields above, security branches, and the
following sections, please visit
<URL:http://www.freebsd.org/security/>.

I.   Background

The Concurrent Versions System (CVS) is a version control system.  It
may be used to access a repository locally, or to access a `remote
repository' using a number of different methods.  When accessing a
remote repository, the target machine runs the CVS server to fulfill
client requests.

II.  Problem Description

Multiple programming errors were found in CVS.  In one case, variable
length strings are copied into a fixed length buffer without adequate
checks being made; other errors include NULL pointer dereferences,
possible use of uninitialized variables, and memory leaks.

III. Impact

CVS servers ("cvs server" or :pserver: modes) are affected by these
problems.  The buffer overflow may potentially be exploited to execute
arbitrary code on the CVS server, either in the context of the
authenticated user or in the context of the CVS server, depending on
the access method used.  The other errors may lead to a denial of
service.

IV.  Workaround

No workaround is available for cvs servers; cvs clients are unaffected.

V.   Solution

Perform one of the following:

1) Upgrade your vulnerable system to 4-STABLE or 5-STABLE, or to the
RELENG_5_3, RELENG_4_11, or RELENG_4_10 security branch
dated after the correction date.

2) To patch your present system:

The following patches have been verified to apply to FreeBSD 4.10,
4.11, and 5.3 systems.

a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.

[FreeBSD 4.10]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:05/cvs410.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:05/cvs410.patch.asc

[FreeBSD 4.11 and 5.3]
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:05/cvs.patch
# fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:05/cvs.patch.asc

b) Execute the following commands as root:

# cd /usr/src
# patch < /path/to/patch
# cd /usr/src/gnu/usr.bin/cvs
# make obj && make depend && make && make install

VI.  Correction details

The following list contains the revision numbers of each file that was
corrected in FreeBSD.

Branch                                                                                                    
                         Path                                                                            Revision
--------------------------------------------------------------------------------------------------------

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

VII. References

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0753
http://secunia.com/advisories/14976/
http://xforce.iss.net/xforce/xfdb/20148