php security blog

WebGoat is a insecure web application which is designed to teach web application security concepts.
You can try hacking: Access Control Flaws, Authentication Flaws, Session Management Flaws, Cross-Site Scripting (XSS), Buffer Overflows, Injection Flaws, Improper Error Handling, Insecure Storage, Denial of Service, Insecure Configuration, Web Services and AJAX Security.

There is a “Lesson Plan” a kind of tutorial and in the “Hints Menu” you can view the parameters, cookies, the Code and the solution.
It’s a lot of fun and you learn more about web application security.

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If there is a reason why you don’t want humans to read your JavaScript code, you can use the packer from
http://dean.edwards.name/packer/ to obfuscated it (online).

The packer compress the code to one line, deletes all comments and has the option to encode it with Base62. You can put the generated code in your code, it should work with any browser.
You must correctly terminate all JavaScript statements with semi-colons.

Here an example script and the output from the packer:
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I had positive feedback after posting my article about hardening Joomla!, so I will now focus on the blog-software wordpress.
Here are a couple of tips that you can use to make your wordpress a bit securer.

Change the default name of your administrator login (admin) and choose a strong password for all your accounts. It’s also a good idea to use different login- and author-names, wordpress has also a great user levels.
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I played last night with a backdoor shell that I found on the net and will show you how this works and how you can find traces if you are the system administrator.

I used 2 vm’s (virtual machines), both based on Debian/Linux one called “victim” it simulates the cracked server where the backdoor runs and the other box called “hacky” where the bad guy is sitting in front :)

The first step of the bad guy is to start a server that listens on some port (12345) on his box, a good program for this is netcat, the command could be something like: netcat -l -p 12345

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I’m not a big fan of Joomla! but a client wanted to use it and so I had a closer look on it, to make it a bit securer.
For the moment I work with the 1.0.14 version and read that the Joomla1.5 work with safe mode on and has some nice security features.
Here are some tips which you can also use if you aren’t a Joomla head.

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I’m a big fan of the open source philosophy but sometimes it’s useful to have an unreadable binary source code.
In this posting i will show you how to use and how to install bcompiler to encode your scripts in phpbytecode, enabling you to protect the source code.
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Akismet, or Automattic Kismet, is a text spam filtering service created by Automattic, the corporation which employs most of the main developers of WordPress.

When a new comment is posted on your site, Akismet webs service catches the comment and tests whether a comment is valued as “spam” or “not spam”. Read more »

.htaccess (hypertext access) is the default name of Apache’s directory-level configuration file. .htaccess is placed in a particular directory, and the directives in the .htaccess file apply to that directory, and all subdirectories thereof.

The most common feature is to restrict access to a folder by force the user to a login prompt, but there are some other helpful things also that I show you in this posting.

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The null byte (also null terminator) is a character with the value zero, present in the ASCII and Unicode character sets. Strings end if there is a null character.
In PHP this character looks like this %00.

Ok whats the deal with null bytes?

A lot of people think that this method below, to include a file which has a fix extension (.php), is a bullet prof one, but that’s not true.

If you call the script with a null byte in the URL it’s possible to include any local or remote site!

http://example.com/?site=../../../../etc/passwd%00

In part 1 we made sure that the value is an integer, but what if a value could be a string?
You have to escape special characters in a string for using in a SQL statement. This means that a single quote (’) get a backslash before (\’).

There are escape functions for each popular database:

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