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Showing posts with the label scanning

An explanation of webserver logs that contain requests such as "\x16\x03\x01"

Recently I have started coming across somewhat unusual entries in the access and error logs for a few of the Apache web servers that I am responsible for maintaining. The entries look like this: - - [03/Nov/2015:13:56:23 -0500] "\x16\x03\x02\x01o\x01" 400 226 "-" "-" Here is another example: - - [03/Nov/2015:23:48:54 -0500] "\x16\x03\x01" 400 226 "-" "-" These errors will be generated on a website configured to use SSL - and in fact, error messages similar to these can be generated by misconfiguring SSL for your website. This error message, for instance, can indicate an attempt to access Apache through SSL while the OpenSSL engine is either disabled or misconfigured: Invalid method in request \x80g\x01\x03 Connections that generate that error would not be successful. This post, however, assumes that your website is working normally when used normally. So what gives? The error indicates

GoDaddy Has Hosted Malicious and Abusive Traffic for over a Year and Doesn't Care

A little over two weeks ago I attempted to contact GoDaddy's Abuse contact about malicious scanning coming from a GoDaddy IP. This post will describe how GoDaddy not only ignored my warnings about this criminal use of their IP space, but has allowed this same scammer to use this same IP to exploit legitimate users for years, ignoring numerous warnings from their own customers, industry security experts and even other hosting companies. I will also explore some possible reasons as to why GoDaddy has become a so-called "Bullet-Proof" host; an honor usually reserved for basement "data centers" from Southeast Asia and Eastern Europe. This IP tried to scan my server for Wordpress vulnerabilities, and then tried to scrape some content. The traffic was ham-fisted and amateurish; the kind of traffic that is obviously malicious. The attempt was logged, immediately blacklisted, and forwarded to me. This sort of thing happens all the time. And ordinarily, I am very sym

RedIRIS Compromised?

For those not familiar with Spanish ISPs, RedIRIS is Spain's  National Research and Education Network . They are part of  Consorci de Serveis Universitaris de Catalunya and  Forum of Incident Response and Security Teams .  Essentially its an organization devoted to university networking projects and advanced R&D. They get their own nice big netblock to mess around with (in this case . Similar projects in the US would be CalREN, Internet2 and LambdaRail.  I'm seeing what looks like malicious scanning from the RedIRIS netblock, like this: ** ** - - [08/Sep/2014:18:54:34 -0400] "GET /muieblackcat HTTP/1.1" 404 15 "-" "-" ** ** - - [08/Sep/2014:18:54:34 -0400] "GET //phpMyAdmin/scripts/setup.php HTTP/1.1" 404 15 "-" "-" ** ** - - [08/Sep/2014:18:54:34 -0400] "GET //phpmyadmin/scripts/setup.php HTTP/1.1" 404 15 "-" "-" ** ** - - [08/Sep/2014:18:54:35 -0400] "G

An Example of Bad Referrer Traffic and How to Block it Using ModRewrite and IPTables

Getting these on one of my web servers on an almost daily basis: - - [01/Sep/2014:09:51:34 -0400] "GET HTTP/1.1" 404 15 "" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.114 Safari/537.36" The traffic comes from all sorts of different IPs that are owned by China Telecom.,,,, The host I am seeing this on does not need to speak to anyone or anything in China, so I used IPTables to filter the entire netblocks I see hits from. Here is an example of a filtering rule along with a little note for myself. Notice that this rule assumes two nonstandard chains - BLACKLIST and LOGDROP - that I use to organize my ruleset. -A BLACKLIST -s -m comment --comment "Chinanet Hotel Qunar Referrer" -j LOGDROP Beca