PHP Include Security

[cremesoda201]

When working on something today, I noticed that any user working with PHP can include any file, regardless of what account it's under. Is this a security risk? If so, how can I fix it?

Example: Two accounts: account1, account2

account1 has a php script on:
/home/account1/public_html/script.php

that is able to include a file such as
include("/home/account2/public_html/random.php");
with success.

Might be a dumb question, but I haven't found any answers yet.

Thanks for any help.

[barns101]

open_basedir: Limit the files that can be opened by PHP to the specified directory-tree, including the file itself. This directive is NOT affected by whether Safe Mode is turned On or Off.

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