FreeBSD Security Advisory FreeBSD-SA-08:12.ftpd

Type securityvulns
Reporter Securityvulns
Modified 2009-01-11T00:00:00



============================================================================= FreeBSD-SA-08:12.ftpd Security Advisory The FreeBSD Project

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

Category: core Module: ftpd Announced: 2008-12-23 Credits: Maksymilian Arciemowicz Affects: All supported versions of FreeBSD. Corrected: 2008-12-23 01:23:09 UTC (RELENG_7, 7.1-PRERELEASE) 2008-12-23 01:23:09 UTC (RELENG_7_1, 7.1-RC2) 2008-12-23 01:23:09 UTC (RELENG_7_0, 7.0-RELEASE-p7) 2008-12-23 01:23:09 UTC (RELENG_6, 6.4-STABLE) 2008-12-23 01:23:09 UTC (RELENG_6_4, 6.4-RELEASE-p1) 2008-12-23 01:23:09 UTC (RELENG_6_3, 6.3-RELEASE-p7) CVE Name: CVE-2008-4247

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I. Background

ftpd(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 ftpd(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 ftpd(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 ftp(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.

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.



b) Execute the following commands as root:

cd /usr/src

patch < /path/to/patch

cd /usr/src/libexec/ftpd

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 Revision Path

RELENG_6 src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c RELENG_6_4 src/UPDATING 1.416. src/sys/conf/ src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c RELENG_6_3 src/UPDATING 1.416. src/sys/conf/ src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c RELENG_7 src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c RELENG_7_1 src/UPDATING 1.507. src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c RELENG_7_0 src/UPDATING 1.507. src/sys/conf/ src/libexec/ftpd/ftpcmd.y src/libexec/ftpd/extern.h src/libexec/ftpd/ftpd.c


Branch/path Revision

stable/6/ r186405 releng/6.4/ r186405 releng/6.3/ r186405 stable/7/ r186405 releng/7.1/ r186405 releng/7.0/ r186405

VII. References

The latest revision of this advisory is available at -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (FreeBSD)

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