FreeBSD Security Advisory FreeBSD-SA-09:01.lukemftpd

2009-01-09T00:00:00
ID SECURITYVULNS:DOC:21115
Type securityvulns
Reporter Securityvulns
Modified 2009-01-09T00:00:00

Description

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1

============================================================================= FreeBSD-SA-09:01.lukemftpd Security Advisory The FreeBSD Project

Topic: Cross-site request forgery in lukemftpd(8)

Category: core Module: lukemftpd Announced: 2009-01-07 Credits: Maksymilian Arciemowicz Affects: All supported versions of FreeBSD. Corrected: 2009-01-07 20:17:55 UTC (RELENG_7, 7.1-STABLE) 2009-01-07 20:17:55 UTC (RELENG_7_1, 7.1-RELEASE-p1) 2009-01-07 20:17:55 UTC (RELENG_7_0, 7.0-RELEASE-p8) 2009-01-07 20:17:55 UTC (RELENG_6, 6.4-STABLE) 2009-01-07 20:17:55 UTC (RELENG_6_4, 6.4-RELEASE-p2) 2009-01-07 20:17:55 UTC (RELENG_6_3, 6.3-RELEASE-p8) CVE Name: CVE-2008-4247

For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:http://security.FreeBSD.org/>.

I. Background

lukemftpd(8) is a general-purpose implementation of File Transfer Protocol (FTP) server that is shipped with the FreeBSD base system. It is not enabled in default installations but can be enabled as either an inetd(8) server, or a standard-alone server.

A cross-site request forgery attack is a type of malicious exploit that is mainly targeted to a web browser, by tricking a user trusted by the site into visiting a specially crafted URL, which in turn executes a command which performs some privileged operations on behalf of the trusted user on the victim site.

II. Problem Description

The lukemftpd(8) server splits long commands into several requests. This may result in the server executing a command which is hidden inside another very long command.

III. Impact

This could, with a specifically crafted command, be used in a cross-site request forgery attack.

FreeBSD systems running lukemftpd(8) server could act as a point of privilege escalation in an attack against users using web browser to access trusted FTP sites.

IV. Workaround

No workaround is available, but systems not running FTP servers are not vulnerable. Systems not running the FreeBSD lukemftpd(8) server are not affected, but users of other ftp daemons are advised to take care since several other ftp daemons are known to have related bugs.

NOTE WELL: lukemftpd(8) is a different implementation of an FTP server than ftpd(8).

V. Solution

Perform one of the following:

1) Upgrade your vulnerable system to 6-STABLE, or 7-STABLE, or to the RELENG_7_1, RELENG_7_0, RELENG_6_4, or RELENG_6_3 security branch dated after the correction date.

2) To patch your present system:

The following patches have been verified to apply to FreeBSD 6.3, 6.4, 7.0, and 7.1 systems.

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

fetch http://security.FreeBSD.org/patches/SA-09:01/lukemftpd.patch

fetch http://security.FreeBSD.org/patches/SA-09:01/lukemftpd.patch.asc

b) Execute the following commands as root:

cd /usr/src

patch < /path/to/patch

cd /usr/src/libexec/lukemftpd

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.

CVS:

Branch Revision Path


RELENG_6 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.5.2.2 src/contrib/lukemftpd/src/extern.h 1.1.1.4.2.2 src/contrib/lukemftpd/src/ftpd.c 1.4.2.2 RELENG_6_4 src/UPDATING 1.416.2.40.2.5 src/sys/conf/newvers.sh 1.69.2.18.2.8 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.5.2.1.6.1 src/contrib/lukemftpd/src/extern.h 1.1.1.4.2.1.6.1 src/contrib/lukemftpd/src/ftpd.c 1.4.2.1.6.2 RELENG_6_3 src/UPDATING 1.416.2.37.2.13 src/sys/conf/newvers.sh 1.69.2.15.2.12 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.5.2.1.4.1 src/contrib/lukemftpd/src/extern.h 1.1.1.4.2.1.4.1 src/contrib/lukemftpd/src/ftpd.c 1.4.2.1.4.1 RELENG_7 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.6.2.1 src/contrib/lukemftpd/src/extern.h 1.1.1.5.2.1 src/contrib/lukemftpd/src/ftpd.c 1.5.2.1 RELENG_7_1 src/UPDATING 1.507.2.13.2.4 src/sys/conf/newvers.sh 1.72.2.9.2.5 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.6.6.1 src/contrib/lukemftpd/src/extern.h 1.1.1.5.6.1 src/contrib/lukemftpd/src/ftpd.c 1.5.6.2 RELENG_7_0 src/UPDATING 1.507.2.3.2.12 src/sys/conf/newvers.sh 1.72.2.5.2.12 src/contrib/lukemftpd/src/ftpcmd.y 1.1.1.6.4.1 src/contrib/lukemftpd/src/extern.h 1.1.1.5.4.1 src/contrib/lukemftpd/src/ftpd.c 1.5.4.1


Subversion:

Branch/path Revision


stable/6/ r186872 releng/6.4/ r186872 releng/6.3/ r186872 stable/7/ r186872 releng/7.1/ r186872 releng/7.0/ r186872


VII. References

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-4247 http://security.freebsd.org/advisories/FreeBSD-SA-08:12.ftpd.asc

The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-09:01.lukemftpd.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (FreeBSD)

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