Linux Advisory Watch – August 29, 2005

By
-
52

Author: Benjamin D. Thomas

This week, advisories were released for amd64, fetchmail, Mozilla, heartbeat,
clamav, lam, vim, evolution, audit, evolution, mc, kdeaddons, kdeadmin, kdebase,
kdedu, kdegames, kdegraphics, kdemultimedia, kdenetwork, kdepim, kdesdk, kdetoys,
kdeutils, kdevelop, kdewebdev, koffice, xpdf, arts, kdepim, epiphany, kdbg,
doxygen, ncpfs, gaim, pcre, tar, vnc, metacity, cups, pygtk, shadow-utils, and
netpbm. The distributors include Debian, Fedora, Gentoo, an Red Hat.Hacks From Pax: PHP Web Application Security, Part II

Another common cause of PHP application holes is improper sanitization of user
provided data. For example, if you allow a user to fill out a form and then
pass data from a field on that form to a function like system() or exec() the
data could contain something malicious, like an ; rm -rf * command tacked onto
it.

  • Never trust user provided data.
  • Beware functions that launch system commands, think long and hard about checking any data that is passed to them.

Another related but common security flaw in PHP applications is
a SQL injection vulnerability. The magic_quotes_gpc option can
mitigate this, but as with register_globals you should not assume
this setting is on.

For example, in your PHP script you might ask the user for a
user id and password, and then check for the user by passing
the database a query.

SELECT * FROM users WHERE name=’$username’ AND pass=’$password’;

However, if the user logging in is malicious and devious, he
may enter the following as his password:

‘ OR ‘1’=’1

This causes your query to become:

SELECT * FROM users WHERE name=’known_user’ AND pass=” OR ‘1’=’1′;

The user has just logged in with no password, and your
application has been penetrated. To avoid this, check for
the status of magic_quotes_gpc() using the ini_get() function
and if it is disabled, pass all user input that must be included
in a query through addslashes(). This will escape the single
or double quotes in the user input with backslashes, thereby
thwarting the attempted SQL injection attack.

  • Use magic_quotes_gpc, but don’t assume it is on or depend on it.
  • The addslashes() function should be used on user data passed to SQL queries.
  • Again, you simply cannot trust user provided data.

The PHP online manual contains an entire chapter on PHP security. It’s an excellent
resource, and goes into much more detail on the PHP security issues I’ve discussed
in this article. Until next time, stay secure, and don’t blindly trust any user
provided data.

Read Entire Article:
http://www.linuxsecurity.com/content/view/120043/49/

LinuxSecurity.com
Feature Extras:

Linux File
& Directory Permissions Mistakes – One common mistake Linux administrators
make is having file and directory permissions that are far too liberal and
allow access beyond that which is needed for proper system operations. A full
explanation of unix file permissions is beyond the scope of this article,
so I’ll assume you are familiar with the usage of such tools as chmod, chown,
and chgrp. If you’d like a refresher, one is available right here on linuxsecurity.com.

Introduction:
Buffer Overflow Vulnerabilities – Buffer overflows are a leading type
of security vulnerability. This paper explains what a buffer overflow is,
how it can be exploited, and what countermeasures can be taken to prevent
the use of buffer overflow vulnerabilities.

Getting
to Know Linux Security: File Permissions – Welcome to the first
tutorial in the ‘Getting to Know Linux Security’ series. The topic explored
is Linux file permissions. It offers an easy to follow explanation of how
to read permissions, and how to set them using chmod. This guide is intended
for users new to Linux security, therefore very simple. If the feedback is
good, I’ll consider creating more complex guides for advanced users. Please
let us know what you think and how these can be improved.

 

Take advantage of our Linux Security discussion
list! This mailing list is for general security-related questions and comments.
To subscribe send an e-mail to security-discuss-request@linuxsecurity.com
with “subscribe” as the subject.

Thank you for reading the LinuxSecurity.com
weekly security newsletter. The purpose of this document is to provide our readers
with a quick summary of each week’s most relevant Linux security headline.

   Debian
  Debian: New amd64 packages fix several
bugs
  11th, August, 2005

Updated package.
 
  Debian: New fetchmail packages fix arbitrary
code execution
  12th, August, 2005

Updated package.
 
  Debian: New Mozilla packages fix frame
injection spoofing vulnerability
  15th, August, 2005

Updated package.
 
  Debian: New heartbeat packages fix insecure
temporary files
  15th, August, 2005

Updated package.
 
  Debian: New clamav packages fix several
problems
  16th, August, 2005

Updated package.
 
  Debian: New Mozilla packages fix frame
injection spoofing vulnerability
  17th, August, 2005

Updated package.
 
   Fedora
  Fedora Core 4 Update: system-config-bind-4.0.0-28_FC4
  11th, August, 2005

Updated package.
 
  Fedora Core 3 Update: system-config-bind-4.0.0-28
  11th, August, 2005

Updated package.
 
  Fedora Core 4 Update: system-config-netboot-0.1.24-1_FC4
  11th, August, 2005

Updated package.
 
  Fedora Core 3 Update: system-config-netboot-0.1.24-1_FC3
  11th, August, 2005

Updated package.
 
  Fedora Core 4 Update: lam-7.1.1-7.FC4
  11th, August, 2005

Updated package.
 
  Fedora Core 3 Update: lam-7.1.1-7.FC3
  11th, August, 2005

Updated package.
 
  Fedora Core 3 Update: vim-6.3.086-0.fc3
  11th, August, 2005

Updated package.
 
  Fedora Core 4 Update: vim-6.3.086-0.fc4
  11th, August, 2005

Updated package.
 
  Fedora Core 4 Update: evolution-data-server-1.2.3-2.fc4
  15th, August, 2005

Updated package.
 
  Fedora Core 4 Update: audit-1.0.2-3.FC4
  15th, August, 2005

This update fixes several problems where the audit system is
used on systems with SE Linux disabled, it provides a sample CAPP configuration,
adds new auditd config option to keep all logs instead of rotating them,
and does some sanity checks on some rules before sending them to the kernel.
 
  Fedora Core 3 Update: evolution-2.0.4-6
  15th, August, 2005

Fix for SITIC Vulnerability Advisory SA05-001
 
  Fedora Core 4 Update: evolution-2.2.3-2.fc4
  15th, August, 2005

Fix for SITIC Vulnerability Advisory SA05-001
 
  Fedora Core 4 Update: mc-4.6.1a-0.11.FC4
  15th, August, 2005

This update cotains the new official release of the GNU/Midnight
Commander 4.6.1.
 
  Fedora Core 3 Update: mc-4.6.1-1.FC3
  15th, August, 2005

This update cotains the new official release of the GNU/Midnight
Commander 4.6.1.
 
  Fedora Core 3 Update: system-config-netboot-0.1.26-1_FC3
  15th, August, 2005

Updated package.
 
  Fedora Core 3 Update: vim-6.3.086-0.fc3.1
  15th, August, 2005

CAN-2005-2368 This update is supposed to fix GTK2 dependency
problems of the vim-6.3.086-0.fc3 package.
 
  Fedora Core 3 Update: kdeaddons-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdeadmin-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdeartwork-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdebindings-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdebase-3.4.2-0.fc3.2
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdeedu-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdegames-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdegraphics-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kde-i18n-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdelibs-3.4.2-0.fc3.2
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdemultimedia-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdenetwork-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdepim-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdesdk-3.4.2-0.fc3.2
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdetoys-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdeutils-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdevelop-3.2.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdewebdev-3.4.2-0.fc3.1
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: koffice-1.4.1-0.FC3.2
  15th, August, 2005

update to 1.4.1
 
  Fedora Core 4 Update: xpdf-3.00-20.FC4.2
  15th, August, 2005

A flaw was discovered in Xpdf in that an attacker could construct
a carefully crafted PDF file that would cause Xpdf to consume all available
disk space in /tmp when opened.
 
  Fedora Core 3 Update: xpdf-3.00-10.6.FC3
  15th, August, 2005

A flaw was discovered in Xpdf in that an attacker could construct
a carefully crafted PDF file that would cause Xpdf to consume all available
disk space in /tmp when opened.
 
  Fedora Core 3 Update: arts-1.4.2-0.fc3.2
  15th, August, 2005

update to KDE 3.4.2
 
  Fedora Core 3 Update: kdeedu-3.4.2-0.fc3.2
  15th, August, 2005

Ben Burton notified the KDE security team about several tempfile
handling related vulnerabilities in langen2kvtml, a conversion script
for kvoctrain.
 
  Fedora Core 3 Update: arts-1.4.2-0.fc3.3
  15th, August, 2005

Update to KDE 3.4.2
 
  Fedora Core 4 Update: kdepim-3.4.2-0.fc4.3
  15th, August, 2005

This update should fix a bug which caused kmail saves attachments
as zero-sized files
 
  Fedora Core 4 Update: epiphany-1.6.5-1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: system-config-netboot-0.1.26-1_FC4
  18th, August, 2005

Updated package.
 
  Fedora Core 3 Update: kdbg-2.0.0-0.fc3.1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: doxygen-1.4.4-0.fc4.1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: kdbg-2.0.0-0.fc4.1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: kdeedu-3.4.2-0.fc4.2
  18th, August, 2005

Ben Burton notified the KDE security team about several tempfile
handling related vulnerabilities in langen2kvtml, a conversion script
for kvoctrain. The script must be manually invoked.
 
  Fedora Core 3 Update: ncpfs-2.2.4-4.FC3.1
  18th, August, 2005

Updated package.
 
  Fedora Core 3 Update: gaim-1.5.0-1.fc3
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: gaim-1.5.0-1.fc4
  18th, August, 2005

Updated package.
 
  Fedora Core 3 Update: system-config-bind-4.0.0-30
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: system-config-bind-4.0.0-30_FC4
  18th, August, 2005

Updated package.
 
  Fedora Core 3 Update: pcre-4.5-3.1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: tar-1.15.1-8.FC4
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: gstreamer-plugins-0.8.8-9
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: vnc-4.1.1-10.1
  18th, August, 2005

This package disables the render patch, which was causing problems
when using the loadable X module.
 
  Fedora Core 3 Update: netpbm-10.28-1.FC3.2
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: metacity-2.10.3-1
  18th, August, 2005

This update of metacity fixes the behavior of minimized transient
dialogs for some applications.
 
  Fedora Core 4 Update: cups-1.1.23-15.1
  18th, August, 2005

These updated packages fix a problem handling PDF files that
could have security implications.
 
  Fedora Core 3 Update: cups-1.1.22-0.rc1.8.6
  18th, August, 2005

These updated packages fix a problem handling PDF files that
could have security implications.
 
  Fedora Core 4 Update: pygtk2-2.6.2-0.fc4.1
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: shadow-utils-4.0.7-10.FC4
  18th, August, 2005

Updated package.
 
  Fedora Core 4 Update: netpbm-10.28-1.FC4.2
  18th, August, 2005

Updated package.
 
   Gentoo
  Gentoo: Gaim Remote execution of arbitrary
code
  15th, August, 2005

Gaim is vulnerable to a buffer overflow which could lead to
the execution of arbitrary code or to a Denial of Service.
 
  Gentoo: AWStats Arbitrary code execution
using malicious Referrer information
  16th, August, 2005

AWStats fails to validate certain log input, which could lead
to the execution of arbitrary Perl code during the generation of the statistics.
 
  Gentoo: Xpdf, Kpdf, GPdf Denial of Service
vulnerability
  16th, August, 2005

Xpdf, Kpdf and GPdf may crash as a result of a Denial of Service
vulnerability.
 
  Gentoo: bluez-utils Bluetooth device
name validation vulnerability
  17th, August, 2005

Improper validation of Bluetooth device names can lead to arbitrary
command execution.
 
   Red
Hat
  RedHat: Critical: Adobe Acrobat Reader
security update
  16th, August, 2005

Updated acroread packages that fix a security issue are now
available. This update has been rated as having critical security impact
by the Red Hat Security Response Team.
 

RELATED ARTICLESMORE FROM AUTHOR