I do things with computers.
Well, unfortunately within hours of updating the BlogEngineDotNet application to the latest version, it resulted in getting hacked. BlogEngineDotNet is a barely functioning Blog Application and Windows 2008 is old, so it’s time to just ditch the stupid and join the 21st Century. Yes, of course I tried running BlogEngineDotNet via Apache and mod_mono but no, it’s so poorly coded it doesn’t work on the Mono platform. Goodbye BlogEngineDotNet, Goodbye Windows Server.
Miracles never cease! BlogEngine.Net has been updated to v3.2. It’s not a bad update. The automated update process went a lot more smoothly, since I knew what to do from the previous one. The Standard-28 theme was removed, so I had to pick a different default theme which is fine and the search widget appears to be missing. I haven’t checked to see if mod_security has been enabled again. I suspect it wouldn’t be working if it has. Now I just wonder what security issues will pop up that will never be announced or properly fixed. I just about gave up on BlogEngine.Net due to nothing happening with it for over a year. I had moved over a couple of sites to a different CMS and was learning it. This new version of BlogEngine.Net will make me want to stick out with it on this domain for a bit more. Depends on how long I want to maintain a Windows server. Windows is fast becoming pay to play operating service which it isn’t worth it anymore.
Oh the joy! More spam from those stupid ass new top level domains to scam people out of their money with worthless crap. By the time you are done reading this I am sure another TLD will sprout it’s spam wings and flood your mail server with it’s nonsense. Because the world is running out of TLDs so that someone can create hundreds of millions of bogus domains every day to harass us with. Yeah, that’s a good sustainable plan. No, nothing to do with making money.
How do we get rid of this stupid shit? It’s easy with Sendmail.
#cd /etc/mail
Edit the ‘access’ file and add the below list. I’ve sorted to make it easy to add more TLDs as they flood you with spam. This will be a weekly if not daily thing so get used to it. And yes, yes there is a .wang TLD.
# TLD Reject accountant REJECT actor REJECT airforce REJECT army REJECT attorney REJECT auction REJECT audio REJECT band REJECT blackfriday REJECT bid REJECT christmas REJECT click REJECT #club REJECT consulting REJECT cricket REJECT dance REJECT date REJECT degree REJECT democrat REJECT dentist REJECT diet REJECT download REJECT engineer REJECT eu REJECT faith REJECT forsale REJECT futbol REJECT gift REJECT gives REJECT guitars REJECT help REJECT hiphop REJECT hosting REJECT lawyer REJECT loan REJECT link REJECT market REJECT men REJECT mortgage REJECT navy REJECT ninja REJECT party REJECT photo REJECT pics REJECT pro REJECT property REJECT rehab REJECT republican REJECT reviews REJECT review REJECT rip REJECT rocks REJECT science REJECT sexy REJECT show REJECT social REJECT software REJECT stream REJECT tattoo REJECT top REJECT trade REJECT us REJECT wang REJECT webcam REJECT win REJECT xyz REJECT
Save the file, make the db files and restart Sendmail.
Updated List as of 02/07/21
This article is about fail2ban and preventing Sendmail brute force password attacks. Also known as fail2ban’s worthless sendmail-auth configuration.
fail2ban comes with a completely worthless sendmail-auth filter. It looks for a failure notification from Sendmail that most likely will never happen anymore as previously the brute force attack would make one connection and issue multiple AUTH commands. This is no longer the case. The brute force attack makes one connection, issues an AUTH command then disconnects and re-connects. This never triggers the Sendmail “possible SMTP attack: command=AUTH” string.
So, what we need to do is something, anything that actually has some sort of real world value, like it actually working? That’d be helpful, right?
#cd /etc/fail2ban/filter.d/
#cp sendmail-auth.conf sendmail-auth.local
Now edit the .local file and replace the worthless regex
failregex = ^%(__prefix_line)s\w{14}: (\S+ )?\[<HOST>\]( \(may be forged\))?: possible SMTP attack: command=AUTH, count=\d+$
With this
failregex = \[<HOST>\] .*to MTA
\[<HOST>\] \(may be forged\)
\[<HOST>\], reject.*\.\.\. Relaying denied
Save the file, then we want to reload fail2ban
# fail2ban-client reload
Well, we learned how to configure Sendmail to send to a specific IP address on a per domain basis. Google and it’s business service e-mail is now by default publishing IPv6 addresses for MX records, it’s almost impossible to do a per domain setup. We do not want to disable IPv6 entirely on the server, but Sendmail keeps sending out via IPv6. How the hell do you make it stop! It’s quite simple but just a refresher since this is a configuration that is out of sight and mind. Remember that Sendmail is really two things. A Daemon (the part that listens for incoming mail) and a Client (the part that sends/relays e-mail). Naturally you have the DAEMON settings by default, but not the CLIENT settings. So here we go.
I have only found one forum post regarding the proper solution to this problem. It appears not to be properly documented and possibly this is changed behavior in a recent update. However, it does make sense. Essentially you need to tell the IPv6 stack to use your IPv4 address.
Edit /etc/mail/sendmail.mc
Look for
DAEMON_OPTIONS(`Port=smtp,Addr=xxx.xxx.xxx.xxx, Name=MTA')dnl
Below the above line add this;
CLIENT_OPTIONS(`Family=inet6,Addr=::ffff:xxx.xxx.xxx.xxx')dnl
Save the file, make the db files and restart Sendmail.
Now, Sendmail will use IPv4 for it’s CLIENT operations.
With the Windows 10 release we are now getting a ton of neck beard ding dong click bait blog posts about it. The big one making the rounds this week is how Windows 10 doesn’t include the ability to play DVD’s and how it’s some sort of evil thing that Microsoft is charging money for the ability to do so. DVD play back requires the MPEG2 decoder which requires a license.
Welcome to the No History Neck Beards. Seeing as we will ignore the entire history of the Windows operating system. Microsoft Windows has never included in the MPEG2 decoder. It ALWAYS has been an add on. The only Windows editions that included this were the Media Center Editions, in which you most likely paid just a little bit more for the license to the MPEG2 decoder. It is possible that many pre-packaged computers from HP, Compaq, Dell had the decoder included because a third party DVD player was installed. Of course our savior neck beards won’t differentiate from that.
More mail servers are now accepted e-mail via IPv6. I have had a dynamically assigned IPv6 block on my Comcast Business account for awhile and I have let Sendmail decide what to use, and about 99.9% of mail is delivered via IPv4. Just recently it appears Comcast has assigned an IPv6 MX record for their mail server. My Sendmail picked this up and now happily attempts to deliver the mail via the IPv6 address. Unfortunately, it is immediately rejected due to the IPv6 address does not have a PTR record. Of course Comcast Business is far behind on assigning IPv6 blocks so there is no way to get a static IPv6 block and a PTR entry.
How do I get Sendmail to deliver to the IPv4 address instead? It’s called the mailertable feature.. You will need this feature enabled in your sendmail.mc file. Most likely it is already enabled.
/etc/mail/sendmail.mc
FEATURE(`mailertable')
Now you need to make an entry into the mailertable file with the domain and IPv4 address. In order to get the IPv4 MX address for the domain you can do so by using the host command. We first look up the main domain name to get the MX records. Then lookup the IPv4 address for the MX record. We now have the IPv4 address to where we want to deliver the mail.
[root@superstar ~]# host comcast.net
comcast.net has address 69.252.80.75
comcast.net mail is handled by 5 mx2.comcast.net.
comcast.net mail is handled by 5 mx1.comcast.net.
[root@superstar ~]# host mx1.comcast.net
mx1.comcast.net has address 96.114.157.80
mx1.comcast.net has IPv6 address 2001:558:fe16:1b::15
We now add these lines to our mailertable file.
/etc/mail/mailertable
.comcast.net esmtp:[96.114.157.80]
comcast.net esmtp:[96.114.157.80]
Don’t forget to issue make to update the db files for Sendmail to see the changes to the mailertable file. And then restart Sendmail. It will now deliver to the specific IPv4 address.
[root@superstar mail]# make [root@superstar mail]# service sendmail restart Redirecting to /bin/systemctl restart sendmail.service
I have noticed a lot of posts on the BlogEngine forum with users having a lot of problems within the Admin area. One even points out the 405 error which is one of the default errors of the Web Application Firewall mod_security. Which works great in IIS. I suspect a lot of people are not aware that there is a version of mod_security for IIS. And so, people constantly search for the solution to their problem when it’s glaring them right in the face. That is, if you know what you are looking for. Hence this post. If you get a “405 Method Not Allowed” error, most likely the mod_security module is enabled. I have found that the default rules that come with mod_security are pretty much incompatible with BlogEngine and I have to disable the module in order to get it working. Otherwise you will need to disable a vast amount of rules in order to get the application functioning properly. It will be a monumental task in creating a BlogEngine ruleset for mod_security. Hopefully some day in most likely an alternate universe will someone sit down and create a ruleset for it.
When updating BlogEngine 3.x with the new updater you may run into some snags like I did. There are some improvements, yet some are ill thought out unfortunately. The first thing I ran into is that the Update process backs up your site. The problem with this is you may have a large amount of data in your media folder. The backup process cannot handle more than a few megabytes of files in this folder until it will fail with an error on the 4th step as “The directory is not empty”. If you get this error, most likely you have too much data to backup in your media folder. I had several gigabytes of video files in the folder which resulted in this error. To correct the problem, back up your media folder and remove the files from it, then proceed with the update. Once the update is completed you can put your media files back.
Also note that if you are using Chrome, once the update is complete, you may need to delete the browsing history and restart Chrome. I had to do this in order to get the Administration menu working properly.
People seem to not want to believe that there are technologically minded people, and those people have been around for a lot longer than they want to believe. Time and again I come across individuals that prescribe to the idea that I can just make shit up about what I am doing online and it will be the truth. Cause, you know, the Internet is magic and just works, or something. It works because thousands of dedicated people slave behind computers and various network devices to make it work. Those people, monitor and keep track of what their devices are doing to make sure they are doing what they are supposed to. So, when those brilliant lying people say things like “I sent that e-mail last night!”. “I called you multiple times over the week!”. We know you are lying! Every service on the Internet has meticulous log files that tell us what the service is doing and who it’s doing it with. We trust the devices we use and maintain everyday over the lying asshole douche bag.