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Debian Linux Security Update: Lighttpd DoS and Gaim Package Remote Security Issues

Debian Linux project released today bug fixes for lighttpd and gaim package.

Gaim packages fix execution of arbitrary code

It was discovered that gaim, an multi-protocol instant messaging client, was vulnerable to several integer overflows in its MSN protocol handlers. These could allow a remote attacker to execute arbitrary code.

lighttpd packages fix multiple DOS issues

Several local/remote vulnerabilities have been discovered in lighttpd, a fast webserver with minimal memory footprint.

a) lighttpd 1.4.18, and possibly other versions before 1.5.0, does not properly calculate the size of a file descriptor array, which allows remote attackers to cause a denial of service (crash) via a large number of connections, which triggers an out-of-bounds access.

b) connections.c in lighttpd before 1.4.16 might accept more connections than the configured maximum, which allows remote attackers to cause a denial of service (failed assertion) via a large number of connection attempts.

How do I fix lighttpd and gaim security issues?

First, update the internal database, enter:
# apt-get update
Install corrected packages, enter:
# apt-get upgrade

Ubuntu Linux Critical OpenSSL and Ruby Vulnerabilities Fix Released

An unpatched security hole in Ubuntu Linux 8.04 LTS operating system could be used by attackers to send a crafted packet and cause a denial of service via application crash in applications linked against OpenSSL to take control of vulnerable servers. Also ruby package can be used to run a malicious script - an attacker could cause a denial of service or execute arbitrary code with the privileges of the user invoking the program. It is recommended that you immediately update your system. Affected systems:
OpenSSL Vulnerability - Ubuntu Linux LTS 8.04 and corresponding versions of Kubuntu, Edubuntu, and Xubuntu.
Ruby Vulnerability - Ubuntu 6.06 LTS Ubuntu 7.04 Ubuntu 7.10 Ubuntu 8.04 LTS and corresponding versions of Kubuntu, Edubuntu, and Xubuntu.

How do I fix this issue

Simply type the following two commands:
$ sudo apt-get update
$ sudo apt-get upgrade

After a standard system upgrade you need to reboot your computer to effect the necessary change:
$ sudo reboot

Security Alert: Ubuntu Linux kernel vulnerabilities

Ubuntu Linux today pushed out a new version of Linux kernel to fix serval local and remote security issues. A malicious CIFS server could cause a client system crash or possibly execute arbitrary code with kernel privileges. On SMP systems, a race condition existed in fcntl(). Local attackers could perform malicious locks, causing system crashes and leading to a denial of service. This security issue affects the following Ubuntu, Kubuntu, Edubuntu, and Xubuntu. releases:

=> Ubuntu 6.06 LTS
=> Ubuntu 7.04
=> Ubuntu 7.10

To fix this issue type the following two commands:
$ sudo apt-get update
$ sudo apt-get upgrade

You need to reboot your computer to effect the necessary changes, enter:
$ sudo reboot

How To Secure Mac OS X Computer ( Hardening Mac )

Apple has released 230 page guide for securing and safeguarding Mac OS X system from the hackers and crackers. The Security Configuration Guides provide an overview of features in Mac OS X that can be used to enhance security, known as hardening your computer. Using this guide you can:

=> Lock down the system.
=> Protect Mac OS x from external attackers.
=> Avoid unauthorized access
=> Secure Mac by hardening your computer.
=> Mac OS X security and much more.

However, guide is heavily depend upon shell prompt (read as terminal) to perform recommended tasks. So you need to have some basic knowledge of terminal. From the Apple site:

Certain instructions in the guides are complex, and deviation could result in serious adverse effects on the computer and its security. The guides should only be used by experienced Mac OS X users, and any changes made to your settings should be thoroughly tested.

Download Mac OS X Security Configuration Guides

Download guide for Mac OS X v10.5 (Leopard) / Mac OS X v10.4 (Tiger) / Mac OS X v10.3 (Panther):

FreeBSD Apache Multiple Vulnerabilities Fix Available

FreeBSD has issued updated version of its Apache package. This release considered as important and encourage users of all prior versions to upgrade.

Cross-site request forgery (CSRF) vulnerability in the balancer-manager in mod_proxy_balancer for Apache HTTP Server 2.2.x allows remote attackers to gain privileges via unpsecified vectors.

The ap_proxy_http_process_response function in mod_proxy_http.c in the mod_proxy module in the Apache HTTP Server 2.0.63 and 2.2.8 does not limit the number of forwarded interim responses, which allows remote HTTP servers to cause a denial of service (memory consumption) via a large number of interim responses.

How do I upgrade Apache under FreeBSD?

Simply run the following two commands:
# portsnap fetch extract
# portupgrade -a
# portversion

PHP Secure Password Hashing

This blog post provides good information about password hashing. The main point of this article is to use strong encryption and make attackers life hard. So if someone gains access to database, attacker could figure out your password using a brute force or rainbow tables.

Is Linux server more secure than Windows server?

Many new Linux user / admin asks:

Is Linux more secure than Windows?

That depends. ;-) Let me explain:

Fan boys on both sides argue to the death that their religion operating system is the best and safest to use.

Windows is harder to secure than Linux. It is the simple truth. Many IT professionals including RHCEs and MCSEs believe that Linux is more secure than Windows. However you cannot blindly accept Linux is more secure than Windows. On both operating systems you need to:
a) Restrict user access
b) Restrict service access
c) Restrict network access
d) Create backup / restore policy
e) Install and manage app level security
f) Continuously install, configure, and patch the system etc

As you see both Windows and Linux administrators requires same levels of skills. Linux is secure by design i.e. Linux is inherently more secure than Windows. Linux designed as a multi-use, network operating system from day one. For example IE / FF bug can take down entire windows computer. However, if there were the same bug in FF it won't take down entire Linux computer. Under windows almost any app level bug (read as vulnerability) can be used to take down the entire system and turn into a zombie computer.

In short,

  1. No operating system is secure
  2. Both Linux / Windows admin requires same level of skills
  3. By default Linux is more secure than Windows, but it is also open to attack.
  4. You can just make attackers job hard.
  5. Remember, security is an on going process and nothing is secure once connected to network, period.

This is based upon my own experience. I don't have a good answer here. What do you think? Do you run Windows and Linux? Please add your experience in the comments.