Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : Disabling fopen("/etc/passwd","r");

[b3nz]

Hello,

I were seeing c99.php source code to know how it gets /etc/passwd file. it simply uses fopen() for this goal but I think fopen() is needed and I don't like it to be disabled in disabled_functions. I wonder how can I disable just fopen("/etc/passwd","r"); without doing any restriction to fopen function at all

any idea will be appreciated

Best Regards.

[Scott.Mc]

Theres no easy method to do this, infact to stop it opening that file specfically you would need to edit the php source.

That will will always be readable by all users on the system, theres nothing really bad about reading it.

The most effective way is going to be to use openbase_dir.

[SparkSupport]

Make sure that you have the entry open_basedir = "/home:/tmp:/usr" in your php.ini. See if it helps

[b3nz]

open_basedir is enabled and has been set to /home:/tmp, I think open_basedir has no restriction to do with fopen().

you're right, there's nothing bad about reading passwd because the passwords will be saved as shadow in most servers but it could reveal user's home directory and etc . anyway, Thank you for your help

[b3nz]

Dear sparksupport, I've already set open_basedir to /home:/tmp

[Scott.Mc]

Originally Posted by b3nz

open_basedir is enabled and has been set to /home:/tmp, I think open_basedir has no restriction to do with fopen().

you're right, there's nothing bad about reading passwd because the passwords will be saved as shadow in most servers but it could reveal user's home directory and etc . anyway, Thank you for your help

If you define openbase_dir within the users virtualhost then yes it will have an effect because they will be unable to read anything outside of the path you specify.

[b3nz]

So why passwd is still readable for c99 ? That's why I got confused

[Scott.Mc]

Show me the openbase_dir entry for that virtualhost.

[b3nz]

That virtualhost got the same rules that has been set in php.ini

This result created by c99 itself :

Server security information:Open base dir: /home:/tmp

Get /etc/passwd

it means open_basedir is currently working on this site but passwd could be read by fopen()