[ GLSA 200403-08 ] oftpd DoS vulnerability

[pahud]

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Gentoo Linux Security Advisory GLSA 200403-08
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http://security.gentoo.org
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Severity: Normal
Title: oftpd DoS vulnerability
Date: March 29, 2004
Bugs: #45738
ID: 200403-08

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Synopsis
========

A remotely-exploitable overflow exists in oftpd, allowing an attacker
to crash the oftpd daemon.

Background
==========

Quote from http://www.time-travellers.org/oftpd/

"oftpd is designed to be as secure as an anonymous FTP server can
possibly be. It runs as non-root for most of the time, and uses the
Unix chroot() command to hide most of the systems directories from
external users - they cannot change into them even if the server is
totally compromised! It contains its own directory change code, so that
it can run efficiently as a threaded server, and its own directory
listing code (most FTP servers execute the system "ls" command to list
files)."

Affected packages
=================

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Package / Vulnerable / Unaffected
-------------------------------------------------------------------
net-ftp/oftpd <= 0.3.6 >= 0.3.7

Description
===========

Issuing a port command with a number higher than 255 causes the server
to crash. The port command may be issued before any authentication
takes place, meaning the attacker does not need to know a valid
username and password in order to exploit this vulnerability.

Impact
======

This exploit causes a denial of service.

Workaround
==========

While a workaround is not currently known for this issue, all users are
advised to upgrade to the latest version of the affected package.

Resolution
==========

All users should upgrade to the current version of the affected
package:

# emerge sync

# emerge -pv ">=net-ftp/oftpd-0.3.7"
# emerge ">=net-ftp/oftpd-0.3.7"

References
==========

[ 1 ] http://www.time-travellers.org/oftpd/oftpd-dos.html

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
http://bugs.gentoo.org.