Should I worry about PHP injection if I don't use MySQL?
<p>I use a simple PHP script to run an online comic which basically uses a GET to take an integer value <i>n</i> and insert an img tag for <i>n</i>.jpg. It doesn't do any sanitizing or error checking beyond making sure that <i>n</i>.jpg exists. The only user interaction with the script is through this GET, and another that does the same thing with a string to manually display a different template for testing.</p>

<p>My question is, should I even be worrying about injection? And if so, what should I do to prevent it? Everything I've found so far only concerns MySQL injection, which doesn't apply in this case.</p>
