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Attacks by ZmEu or w00tw00t robots

Who is ZmEu?

An image showing ZmeuThe name Zmeu (no capital E) is the name of a fantastic creature of Romania. There are so many stories that there isn't a clear understanding of what it is... but it is human like, can spit fire and wants to marry young women.

If you're wondering, it is generally a bad guy.

ZmEu Attack

Today, I noticed a lot of traffic on one of my servers. Looking into what was happening, I immediately found out that an attacker was looking for a loophole in that system. That attack was being performed from China.

Desktop Google Calendar now defaults to Agenda because I have it on my Android...

Since I got my Android phone earlier this year, I got a huge problem with Google Calendar.

I use the calendar mainly on my Desktop. Big screen, easy to read and use. But on the Android, the format is Agenda to make it possible to use at all.

Somehow that has a really bad side effect: the display is now always forced to Agenda on my Desktop too. Really annoying!

Tere is actually a very easy fix! It took me months the discover it and it's actually very easy.

I have the Calendar link bookmarked so I can just click one button to get it open.

All I had to do is add the following anchor at ...

Increasing the volume over 100% on Linux

I have been listening to many videos on YouTube, Facebook, etc. that have a really low volume. This is generally rather annoying since in the end I cannot hear a lot of the audio track.

There is actually a way to increase the volume over the normal 100% limit.

There are several features that offer such a feature, but the one that worked for me is a Volume Control application called pavucontrol.

sudo apt-get install pavucontrol
pavucontrol

It looks like various systems offer various ways to do that, but at least that one works for me under Linux in Ubuntu Unity.

Source: ...

My Embedded YouTube Video Disappeared

Embedded videos from YouTube.com used to work just fine on my website.

Today, though, I just noticed that my video was not showing up on one of my pages. Looking into it, I found out that the problem was the protocol.

I'm not too sure whether it was my browser or YouTube,com (although I'm not too sure how YouTube.com would know...) but the fact is that the iframe source was using HTTP and the page I was viewing used HTTPS.

By editing the page and changing the YouTube.com video from HTTP to HTTPS resolved the issue. It is generally much better to always use encryption anyway.

How to find fail2ban errors when logs/errors don't make it anywhere?

Today I noticed that my fail2ban wasn't running.

Looking into it, I could see that an error was happening on startup. This pretty much always mean that something's wrong in the configuration files.

sudo systemctl start fail2ban
Job for fail2ban.service failed because the control process exited with error code.
See "systemctl status fail2ban.service" and "journalctl -xe" for details.

However, somehow, systemd would not show me the error with the status or checking the journal and it would not write anything to the /var/log/fail2ban.log file which stayed ...

Why are hotmail.com emails blocked by postgrey even though it is whitelisted?

Lately, I received emails from a customer something like 12 hours later...

So I checked closer and could see that the email was from hotmail.com.

Great.

On the server, I edited my whitelist to see what was going on:

vim /etc/postgrey/whitelist_clients.local

Searching the list I could see hotmail.com, so why is it that it gets bounced with a 450 by Postgrey if it is whitelisted?

Looking closer at the logs left behind by Postgrey, I found this line:

Apr 23 06:33:34 m2osw postgrey[1742]: action=greylist,
      reason=new,
      client_name=<secret>.outlook.com,
      ...

Convert XML tags and text to a String

Today I started testing a lot of my JavaScript / jQuery code from a website I am building for a customer. I got an error, at some point, saying:

SCRIPT5007: Unable to get property 'replace' of undefined or null reference

The error was in link with the 'replace' function being referenced on an innerHTML of an element. More specifically, one of those XML element (probably the top most one.)

The fact is that Internet Explorer does not support innerHTML in an XML document. Not to be too surprised about that, XML is not HTML so there is really no reason why innerHTML should be ...

Lost SSH key graphical prompt and auto-add to SSH agent

At some point in the past, my system somehow lost the ability to avoid asking me for my key every time I connect to one of my servers. It generally okay, I don't do so much work on that server that I'd have to connect all the time...

However, it is annoying when, once in while, I end up doing a lot of work, back and forth.

The ssh-agent was installed and working. I could add the key manually:

ssh-add ~/.ssh/my-secret-key
ssh-add -l

The ssh-add command allows you to add and remove keys from the ssh-agent. The -l command line option lists the keys currently held by the agent.

...

xhtml2pdf generating an error under 14.04+

Note: This bug is fixed in Ubuntu 16.04

Working on a website I have to convert invoices to PDF so end users have the ability to print and share the invoices from the website.

In order to do that, I generate an HTML page with the invoice which also gets displayed in the website, and then convert that HTML to PDF with xhtml2pdf. I use that tool instead of whtmltopdf because it does not require X11 to work. The other tool is said to require Qt and X11 and we do not want those things on our backend servers.

So... I upgraded to 14.04 and the tool stopped working with an ugly error:

 ...

List ciphers currently used by Apache2

If you are using Apache and e-Commerce, you probably want to know all the details of the ciphers used by the Apache SSL module.

So listing Apache supported ciphers is done using nmap as follow:

nmap --script ssl-cert,ssl-enum-ciphers -p 443 secure.m2osw.com

This call gives you a complete list of all the ciphers currently accepted by your running version of Apache. For example, the list may look like this:

| ssl-enum-ciphers:
|   SSLv3:
|     ciphers:
|       TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA - strong
|       TLS_DHE_RSA_WITH_AES_128_CBC_SHA - strong
|       ...
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