Category: security

computer security related topic

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Using htaccess to stop Bad Bots from stealing bandwidth and crashing your server

Few days ago my site was hit by a bunch of really bad bots which crawl my site continuously until it overloads my web server. Now I’m publishing a way to block these so-called bad robots from ruining your website by their crazy crawling method.

Assuming you are using Apache Http server, create .httaccess file and append this line to the newly created file.
Continue reading “Using htaccess to stop Bad Bots from stealing bandwidth and crashing your server”

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Intermittent downtime : Between bad bots and DDOS

Few days ago my site has been subjected to bad http crawling bot which caused my site to be slower than usual. It become worse when somebody took advantage of the situation and launch a Denial-of-Service attack to my website which effectively took my website down for few hours per-day until today.

Rest assured the culprits has been identified and has been dealt with, you can enjoy reading my blog again. I’ve made few modification to my sites so it is more resistant to this sort of problem the next time around.

I sincerely apologize to those who have been subjected to hours of waiting for my site to load (and viewing the dreaded Internal Server Error messages) for the past 3-4 days.

And for those who are wondering about Gutsy Gibbon update will be able to read them at my personal blog : http://please.name.my.

Have fun !

[tags]gutsy,gutsy gibbon,ubuntu,feisty,feisty fawn,ddos,downtime,dreamhost,bots,bad bots[/tags]

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Why newbies still use outdated Red Hat Linux 9 ?

I’m writing this because I found out that many Linux newbie still prefer to use Red Hat Linux 9 compared to Fedora Core distribution.

Red Hat Linux 9 has been released in 2003, and between that year and at the time of this writing, Red Hat Linux 9 has been superseded by almost 6 newer releases (Fedora Core 1 – Fedora Core 6, Fedora 7 if you want to count that too)

Red Hat Linux 9 has been long abandoned by Red Hat when it discontinued its support in April 2004 (3 years ago) in favor of Community maintained Fedora Core line (now Fedora) .

To show you that how much technology has changed since its release, Red Hat 9 includes linux kernel 2.4.20, mozilla browser 1.2.1, openoffice 1.0.2 as opposed to the latest distribution which includes linux kernel 2.6.19, (or 2.4.34, if you count the 2.4 branches) mozilla 1.8.x.

One might wonder how many security holes left unfixed when Red Hat stopped providing security patches to the operating system since April 2004 (three years ago).

What makes people (especially by newbies) still use Red Hat Linux 9 ?

  • Red Hat Linux is the most popular Linux distribution during late 1990s and early 2000
  • Red Hat made a terrible rebranding move, it rebrands Red Hat Linux to a completely new name Fedora Core.
  • There are still lots of older “Linux for beginner” books that make reference to Red Hat Linux (7.0,7.1,7.3,8.0), this left an impression to newbies that Red Hat Linux 9 is the latest ‘Linux’ release (old book stock with free RH9 CDs is the main culprit)
  • Newbies trust the content in the books 100% without taking account that computer software books has an ‘unofficial expiry date’, they should have done more research through the internet.

Implication of using Red Hat Linux 9

  • People will get the wrong impression about Linux, based on outdated technology
    Drivers support is not up to date with the current hardware (not much wifi support, unstable drivers)
  • Old software which is buggy and crash prone
  • Outdated Server softwares with tons of security vulnerabilities or even with outdated configuration file.
  • Support websites which do not exists anymore, people will get lost without proper documentation
  • No software updates support.
  • Broken software due to changes in communication protocol (gaim msn, yahoo messenger, up2date, etc)
  • Primitive software (that do not conforms with the latest trend) that may cause data loss

So please ditch the idea of using Red Hat 9 as your first distro and use latest Linux distro release for your own good, things changed a lot since RH9 been released.

norh9.png

Say no to Red Hat 9 :p

[tags]red hat, red hat linux,redhat,linux,debian,yum,ubuntu,kernel,distro[/tags]

Posted on

How to secure your SSH server

I came across this interesting post about how to secure your SSH without changing the SSH listening port.

Things that the post author suggested are :

  1. Enforce the use of secure and hard to guess password
  2. Disable login by password, use Public Key Authentication for greater security.
  3. Allow SSH connection from trusted network only.
  4. Implement Port Knocking – http://www.linuxjournal.com/article/6811
  5. Use iptables RECENT match to filter SSH scanners

Personally I’ve enabled public-key authentication and SSH scanner filter to secure my server at the advice of my friend from a local security firm. Although, I haven’t tried the port knocking method yet, it seems interesting to know that ‘secret port knocking’ pattern also exists in computer security (remember ali baba?)

Hopefully this post will serve as a reminder to myself and those who read them, ah oh, most of this post content are lifted shamelessly from False sense of security

[tags]ssh,iptables,ubuntu,debian,security, port knocking,nmap, security scanners,exploit[/tags]

http://blog.drinsama.de/erich/en/linux/2007021502-false-sense-of-security