Tag: Security

phpMyAdmin lets you easily manage your MySQL databases, and as such it also presents a security risk. Logging in to phpMyAdmin is done using a username and password for the database. Hence, if someone is able to either eavesdrop or guess them by brute force, they could wreak havoc on your server.

A possible solution to the eavesdropping problem is to use SSL to secure communication to phpMyAdmin. However, SSL certificates don’t provide any method to stop brute-forcing. To prevent brute-force attempts, you could limit access to your IP address. However, most of us don’t have static IPs at home. The solution I came up with kind of combines both approaches.

Instead of using SSL to encrypt the data sent, I’m using SSH, and instead of limiting access to my IP address, I’ll limit access to the server’s IP address. How will it work? First, we start by editing the phpMyAdmin configuration for lighttpd. This usually resides in /etc/lighttpd/conf-enabled/50-phpmyadmin.conf. At the top of the file you’ll find the following lines:

alias.url += (
        "/phpmyadmin" => "/usr/share/phpmyadmin",
)

These lines define the mapping to the phpMyAdmin installation; without them, phpMyAdmin wouldn’t be accessible. We use lighttpd’s conditional configuration to limit who is able to use that mapping by changing the above lines to:

$HTTP["remoteip"] == "85.25.120.32" {
        alias.url += (
                "/phpmyadmin" => "/usr/share/phpmyadmin",
        )
}

This limits access to phpMyAdmin only to clients whose IP is the server’s IP (of course you’ll need to change that IP to your server’s IP). This curtails any brute-force attempts, as only someone trying to access phpMyAdmin from the server itself will succeed.

But how can we “impersonate” the server’s IP when we connect from home? The easiest solution would be to use the SOCKS proxy provided by SSH.

ssh user@server.com -D 1080

This will set up a SOCKS proxy on port 1080 (locally) that will tunnel traffic through your server. The next step is to instruct your browser or OS to use that proxy (in Firefox it can be done via Preferences->Advanced->Network->Connection Settings; it can also be defined globally via Network Settings->Network Proxy under GNOME). This achieves both of our goals. We are now able to connect to the server while using its own IP, and our connection to the server is encrypted using SSH.

This method can be used to secure all kinds of sensitive applications. We could have achieved the same thing by using a VPN, but it’s more hassle to set up compared to SSH, which is available on any server.