Improve Site Security by Protecting HTAccess Files

.htaccess made easy

As you know, HTAccess files are powerful tools for manipulating site performance and functionality. Protecting your site’s HTAccess files is critical to maintaining a secure environment. Fortunately, preventing access to your HTAccess files is very easy. Let’s have a look..

Different Methods

If you search around the Web, you will probably find several different methods of protecting your HTAccess files. Here are a few examples, along with a bit of analysis:

Case-sensitive protection — As far as I know, this is the most widespread method of protecting HTAccess files. Very straightforward, this code will prevent anyone from accessing any file named precisely “.htaccess”. This is not ideal because the match is case sensitive. On certain systems, HTAccess files protected with this method may remain accessible via “HTACCESS”, for example.

# CASE SENSITIVE METHOD
<Files .htaccess>
 order allow,deny
 deny from all
</Files>

Weak pattern matching — Recently, I have been seeing several instances of this particular technique. Using the same general strategy, this method will prevent access to any file beginning with the characters “.ht”. The assumption here is that HTAccess files are the only files that begin with “.ht”. Thus, by simply matching these first three characters, all HTAccess files — and only HTAccess files — will be protected from external access. Unsafe assumptions aside, this method also relies on a case-sensitive match in order to work. Note, however, the addition of the “Satisfy All” directive in the penultimate line — this is an improvement over the previous method.

# WEAK PATTERN MATCHING
<Files ~ "^\.ht">
 Order allow,deny
 Deny from all
 Satisfy All
</Files>

Strong pattern matching — This is the method that I use here at Perishable Press. Using strong pattern matching, this technique prevents external access to any file containing “.hta”, “.HTA”, or any case-insensitive combination thereof. To illustrate, this code will prevent access through any of the following requests:

  • .htaccess
  • .HTACCESS
  • .hTaCcEsS
  • testFILE.htaccess
  • filename.HTACCESS
  • FILEROOT.hTaCcEsS

..etc., etc. Clearly, this method is highly effective at securing your site’s HTAccess files. Further, this technique also includes the fortifying “Satisfy All” directive. Note that this code should be placed in your domain’s root HTAccess file:

# STRONG HTACCESS PROTECTION
<Files ~ "^.*\.([Hh][Tt][Aa])">
 order allow,deny
 deny from all
 satisfy all
</Files>

Suggestionz

Can you improve on this technique? How do you protect your HTAccess files? Speak up!