Image courtesy of eChunks.com Here is a quick security tip for people using popular apps on the Web. That is, apps like WordPress that may be widely used and targeted by bad actors and/or automated scripts. It’s all about adding another layer of security by hardening admin-level usernames.. Every now and then, I get an email letting me know that someone has requested a password reset for one of my admin-level WordPress accounts. Usually, the email notifications are sent directly […] Continue reading »
One of the most annoying, persistent scans I’ve seen in a long time are those hunting for the revslider vulnerability. In the five or so months since the exploit was discovered, many sites have been compromised. And based on what I’ve been seeing in my traffic logs, the risk is far from over. Apparently every 2-bit script kiddie and their pet hamster wants a piece of the “revslider action”. Continue reading »
Whether you like it or not, there are scripts and bots out there hammering away at your sites with endless HTTP “POST” requests. POST requests are sort of the opposite of GET requests. Instead of getting some resource or file from the server, data is being posted or sent to it. To illustrate, normal surfing around the Web involves your browser making series of GET requests for all the resources required for each web page. HTML, JavaScript, CSS, images, et […] Continue reading »
Just as there are specifications for designing with CSS, HTML, and JavaScript, there are specifications for working with URIs/URLs. The Internet Engineering Task Force (IETF) clearly defines these specifications in RFC 3986: Uniform Resource Identifier (URI): Generic Syntax. Within that document, there are guidelines regarding which characters may be used safely within URIs. This post summarizes the information, and encourages developers to understand and implement accordingly. Continue reading »
A reader recently brought to my attention a reported vulnerability on servers running PHP. It’s been known about for eons, but it’s new to me and it involves easter eggs in PHP so I thought it would be fun to share a quick post about what it is and how to prevent leakage of sensitive information about your server. It only takes a moment to disable the easter-egg information, should you decide to do so. Continue reading »
Just a heads up to anyone else getting the occasional PayPal phishing spam.. Usually it’s pretty easy to spot one of those crafty phishing emails, just hover over any links before clicking to view the real URL in the status bar. You know, the link says something like, “click here to restore your PayPal account,” but you know that’s garbage and could easily prove it by checking the actual link URL, which is usually something completely bonkers, like: Continue reading »
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 »
Stolen content is the bane of every blogger who provides a publicly available RSS feed. By delivering your content via feed, you make it easy for scrapers to assimilate and re-purpose your material on their crap Adsense sites. It’s bad enough that someone would re-post your entire feed without credit, but to use it for cheap money-making schemes is about as pathetic as it gets. If you’re lucky, the bastards may leave all the links intact, so at least you […] Continue reading »
The shared server on which I host Perishable Press was recently scanned by security software that revealed a significant security risk. Namely, the HTTP request methods TRACE and TRACK were found to be enabled on my webserver. The TRACE and TRACK protocols are HTTP methods used in the debugging of webserver connections. Although these methods are useful for legitimate purposes, they may compromise the security of your server by enabling cross-site scripting attacks (XST). By exploiting certain browser vulnerabilities, an […] Continue reading »
Recently a reader asked about how to password-protect a directory for every specified IP while allowing open access to everyone else. In my article, Stupid htaccess Tricks, I show how to password-protect a directory for every IP except the one specified, but not for the reverse case. In this article, I will demonstrate this technique along with a wide variety of other useful password-protection tricks, including a few from my Stupid htaccess Tricks article. Before getting into the juicy stuff, […] Continue reading »
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 »
The other day, my server crashed and Perishable Press was unable to connect to the MySQL database. Normally, when WordPress encounters a database error, it delivers a specific error message similar to the following: Continue reading »
Given my propensity to discuss matters involving error log data (e.g., monitoring malicious behavior, setting up error logs, and creating extensive blacklists), I am often asked about the best way to go about monitoring 404 and other types of server errors. While I consider myself to be a novice in this arena (there are far brighter people with much greater experience), I do spend a lot of time digging through log entries and analyzing data. So, when asked recently about […] Continue reading »
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 »
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 »
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 »