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 »
I really hate bad robots. When a web crawler, spider, bot — or whatever you want to call it — behaves in a way that is contrary to expected and/or accepted protocols, we say that the bot is acting suspiciously, behaving badly, or just acting stupid in general. Unfortunately, there are thousands — if not hundreds of thousands — of nefarious bots violating our sites every minute of the day. For the most part, there are effective methods available enabling […] Continue reading »
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 »
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 »
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 »
There are two possibilities here: Yahoo!’s Slurp crawler is broken or Yahoo! lies about obeying Robots directives. Either case isn’t good. Slurp just can’t seem to keep its nose out of my private business. And, as I’ve discussed before, this happens all the time. Here are the two most recent offenses, as recorded in the log file for my blackhole spider trap: Continue reading »
Welcome to the Perishable Press “Blacklist Candidate” series. In this post, we continue our new tradition of exposing, humiliating and banishing spammers, crackers and other worthless scumbags.. From time to time on the show, a contestant places a bid that is so absurd and so asinine that you literally laugh out loud, point at the monitor, and openly ridicule the pathetic loser. On such occasions, even the host of the show will laugh and mock the idiocy. Of course, this […] Continue reading »
An ongoing series of articles on the fine art of malicious exploit detection and prevention. Learn about preventing the sneaky mischievous and deceptive practices of some of the worst spammers, scrapers, crackers, and other scumbags on the Internet. Continue reading »
As my readers know, I spend a lot of time digging through error logs, preventing attacks, and reporting results. Occasionally, some moron will pull a stunt that deserves exposure, public humiliation, and banishment. There is certainly no lack of this type of nonsense, as many of you are well-aware. 3G Blacklist Even so, I have to admit that I am very happy with my latest strategy against crackers, spammers, and other scumbags, namely, the 3G Blacklist. Since implementing this effective […] Continue reading »
Hmmm.. Let’s see here. Google can do it. MSN/Live can do it. Even Ask can do it. So why oh why can’t Yahoo’s grubby Slurp crawler manage to adhere to robots.txt crawl directives? Just when I thought Yahoo! finally figured it out, I discover more Slurp tracks in my Blackhole trap for bad spiders: Continue reading »
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 »
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 »
I need your help! I am losing my mind trying to solve another baffling mystery. For the past three or four months, I have been recording many 404 Errors generated from msnbot, Yahoo-Slurp, and other spider crawls. These errors result from invalid requests for URLs containing query strings such as the following: https://example.com/press/page/2/?tag=spam https://example.com/press/page/3/?tag=code https://example.com/press/page/2/?tag=email https://example.com/press/page/2/?tag=xhtml https://example.com/press/page/4/?tag=notes https://example.com/press/page/2/?tag=flash https://example.com/press/page/2/?tag=links https://example.com/press/page/3/?tag=theme https://example.com/press/page/2/?tag=press Note: For these example URLs, I replaced my domain, perishablepress.com with the generic example.com. Turns out that listing the plain-text […] Continue reading »
Welcome to the Perishable Press “Blacklist Candidate” series. In this post, we continue our new tradition of exposing, humiliating and banishing spammers, crackers and other worthless scumbags.. Just under the wire! Even so, this month’s official Blacklist-Candidate article may be the last monthly installment of the series. Although additional BC articles may appear in the future, it is unlikely that they will continue as a regular monthly feature. Oh sure, I see the tears streaming down your face, but think […] Continue reading »
In the now-complete series, Building the 3G Blacklist, I share insights and discoveries concerning website security and protection against malicious attacks. Each article in the series focuses on unique blacklist strategies designed to protect sites transparently, effectively, and efficiently. The five articles culminate in the release of the next generation 3G Blacklist. Here is a quick summary of the entire Building the 3G Blacklist series: Continue reading »