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Web Dev + WordPress + Security
64 posts

Blank Space / Whitespace Character for .htaccess

Working on the next version of the G-Series Blacklist, I needed a way to match a wide variety of UTF-8-encoded (hex) character strings. Those familiar with their site’s traffic will recognize this particular type of URI request string, which is typically associated with malicious server scanning, exploits, and other malicious behavior. As I explain in this post, pattern-matching and blocking the blank-space, or whitespace character in URL-requests is an effective way to improve the security of your website. Continue reading »

htaccess Redirect to Maintenance Page

Redirecting visitors to a maintenance page or other temporary page is an essential tool to have in your tool belt. Using HTAccess, redirecting visitors to a temporary maintenance page is simple and effective. All you need to redirect your visitors is the following code placed in your site’s root HTAccess: # MAINTENANCE-PAGE REDIRECT <ifmodule mod_rewrite.c> RewriteEngine on RewriteCond %{REMOTE_ADDR} !^123\.456\.789\.000 RewriteCond %{REQUEST_URI} !/maintenance.html$ [NC] RewriteCond %{REQUEST_URI} !\.(jpe?g?|png|gif) [NC] RewriteRule .* /maintenance.html [R=302,L] </ifmodule> That is the official copy-&-paste goodness right […] Continue reading »

Stop 404s for Mobile Versions of Your Site

If you’ve been keeping an eye on your 404 errors recently, you will have noticed an increase in requests for nonexistent mobile files and directories, especially over the past year or so. The scripts and bots requesting these files from your server seem to be looking for a mobile version of your site. Unfortunately, they are wasting bandwidth and resources in the process. It has become common to see the following 404 errors constantly repeated in your log files: http://domain.tld/apple-touch-icon.png […] Continue reading »

Is it Secret? Is it Safe?

Whenever I find myself working with PHP or messing around with server settings, I nearly always create a phpinfo.php file and place it in the root directory of whatever domain I happen to be working on. These types of informational files employ PHP’s handy phpinfo() function to display a concise summary of all of your server’s variables, which may then be referenced for debugging purposes, bragging rights, and so on. While this sort of thing is normally okay, I frequently […] Continue reading »

Secure Visitor Posting for WordPress

Normally, when visitors post a comment to your site, specific types of client data are associated with the request. Commonly, a client will provide a user agent, a referrer, and a host header. When any of these variables is absent, there is good reason to suspect foul play. For example, virtually all browsers provide some sort of user-agent name to identify themselves. Conversely, malicious scripts directly posting spam and other payloads to your site frequently operate without specifying a user […] Continue reading »

HTAccess Spring Cleaning 2009

Just like last year, this Spring I have been taking some time to do some general maintenance here at Perishable Press. This includes everything from fixing broken links and resolving errors to optimizing scripts and eliminating unnecessary plugins. I’ll admit, this type of work is often quite dull, however I always enjoy the process of cleaning up my HTAccess files. In this post, I share some of the changes made to my HTAccess files and explain the reasoning behind each […] Continue reading »

4G Series: The Ultimate Referrer Blacklist, Featuring Over 8000 Banned Referrers

You have seen user-agent blacklists, IP blacklists, 4G Blacklists, and everything in between. Now, in this article, for your sheer and utter amusement, I present a collection of over 8000 blacklisted referrers. Shortcut: skip the article and jump to Disclaimer and Download » Referrer Spam Sucks For the uninitiated, in teh language of teh Web, a referrer is the online resource from whence a visitor happened to arrive at your site. For example, if Johnny the Wonder Parrot was visiting the […] Continue reading »

4G Series: The Ultimate User-Agent Blacklist, Featuring Over 1200 Bad Bots

As discussed in my recent article, Eight Ways to Blacklist with Apache’s mod_rewrite, one method of stopping spammers, scrapers, email harvesters, and malicious bots is to blacklist their associated user agents. Apache enables us to target bad user agents by testing the user-agent string against a predefined blacklist of unwanted visitors. Any bot identifying itself as one of the blacklisted agents is immediately and quietly denied access. While this certainly isn’t the most effective method of securing your site against […] Continue reading »

The Perishable Press 4G Blacklist

At last! After many months of collecting data, crafting directives, and testing results, I am thrilled to announce the release of the 4G Blacklist! The 4G Blacklist is a next-generation protective firewall that secures your site against a wide range of automated attacks and other malicious activity. Continue reading »

Building the Perishable Press 4G Blacklist

Last year, after much research and discussion, I built a concise, lightweight security strategy for Apache-powered websites. Prior to the development of this strategy, I relied on several extensive blacklists to protect my sites against malicious user agents and IP addresses. Unfortunately, these mega-lists eventually became unmanageable and ineffective. As increasing numbers of attacks hit my server, I began developing new techniques for defending against external threats. This work soon culminated in the release of a “next-generation” blacklist that works […] Continue reading »

Controlling Proxy Access with HTAccess

In my recent article on blocking proxy servers, I explain how to use HTAccess to deny site access to a wide range of proxy servers. The method works great, but some readers want to know how to allow access for specific proxy servers while denying access to as many other proxies as possible. Fortunately, the solution is as simple as adding a few lines to my original proxy-blocking method. Specifically, we may allow any requests coming from our whitelist of […] Continue reading »

Eight Ways to Block and Redirect with Apache’s mod_rewrite

With the imminent release of the next series of (4G) blacklist articles here at Perishable Press, now is the perfect time to examine eight of the most commonly employed blacklisting methods achieved with Apache’s incredible rewrite module, mod_rewrite. In addition to facilitating site security, the techniques presented in this article will improve your understanding of the different rewrite methods available with Apache mod_rewrite. Note: I changed the title of this post from “Eight Ways to Blacklist..” to “Eight Ways to […] Continue reading »

Redirect All (Broken) Links from any Domain via HTAccess

Here’s the scene: you have been noticing a large number of 404 requests coming from a particular domain. You check it out and realize that the domain in question has a number of misdirected links to your site. The links may resemble legitimate URLs, but because of typographical errors, markup errors, or outdated references, they are broken, leading to nowhere on your site and producing a nice 404 error for every request. Ugh. Or, another painful scenario would be a […] Continue reading »

Redirecting Subdirectories to the Root Directory via HTAccess

One of the most useful techniques in my HTAccess toolbox involves URL redirection using Apache’s RedirectMatch directive. With RedirectMatch, you get the powerful regex pattern matching available in the mod_alias module combined with the simplicity and effectiveness of the Redirect directive. This hybrid functionality makes RedirectMatch the ideal method for highly specific redirection. In this tutorial, we will explore the application of RedirectMatch as it applies to one of the most difficult redirect scenarios: redirecting all requests for a specific […] Continue reading »

Redirect All Requests for a Nonexistent File to the Actual File

In my previous article on redirecting 404 requests for favicon files, I presented an HTAccess technique for redirecting all requests for nonexistent favicon.ico files to the actual file located in the site’s web-accessible root directory: # REDIRECT FAVICONZ <ifmodule mod_rewrite.c> RewriteCond %{THE_REQUEST} favicon.ico [NC] RewriteRule (.*) http://domain.tld/favicon.ico [R=301,L] </ifmodule> As discussed in the article, this code is already in effect here at Perishable Press, as may be seen by clicking on any of the following links: Update: I’ve removed the […] Continue reading »

Stop the Madness: Redirect those Ridiculous Favicon 404 Requests

For the last several months, I have been seeing an increasing number of 404 errors requesting “favicon.ico” appended onto various URLs: http://example.com/favicon.ico http://example.com/2007/06/12/favicon.ico http://example.com/2007/09/25/absolute-horizontal-and-vertical-centering-via-css/favicon.ico http://example.com/2007/08/01/temporary-site-redirect-for-visitors-during-site-updates/favicon.ico http://example.com/2007/01/16/maximum-and-minimum-height-and-width-in-internet-explorer/favicon.ico When these errors first began appearing in the logs several months ago, I didn’t think too much of it — “just another idiot who can’t find my site’s favicon..” As time went on, however, the frequency and variety of these misdirected requests continued to increase. A bit frustrating perhaps, but not serious enough to […] Continue reading »

Welcome
Perishable Press is operated by Jeff Starr, a professional web developer and book author with two decades of experience. Here you will find posts about web development, WordPress, security, and more »
Banhammer: Protect your WordPress site against threats.
Thoughts
LOL @ “weekly” support: “Your request has been received and will be reviewed soon. Neil (your support guy) checks support requests weekly. Rest assured we’ll get to it!” — Gotta be kidding with this.
After several days of work, finally taking a break. If anyone needs me, I'll be in Zora’s Domain, working thru Mah Eliya shrine.
Never ever call the client a useless idiot. Even if it’s true.
Inevitable that Google shuts down Feedburner. Maybe this year? Who knows. Here is a nice summary plus alternatives.
There is no way that Marvel can serve up anything better than what they've already done with Infinity saga/Endgame. Knowhere to go but down, sadly.
I built a new search launchpad to make my life easier. So I can search multiple engines quickly and easily.
Updating all muh plugins for WP 5.5 imminent release! Wut August :)
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