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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.

CRON Drupal says "HTTP/1.0 302 Found" about "/cgi-bin/ipdiags.ha" (AT&T U-Verse)

I run a few Drupal website and once per hour I run the cron.php script. I do it only once per hour because nothing changes so often on my websites so it would require faster refreshes.

Once in a while (relatively rarely now) I get a list of errors from CRON saying that the checks failed. The errors look something like this:

HTTP/1.0 302 Found
Location: /cgi-bin/ipdiags.ha
Pragma: no-cache
Content-Type: text/html

<html><meta http-equiv=Refresh content=0;url=/cgi-bin/ipdiags.ha>

As you can see, this is a 302 so a temporary error. ...

Repair a Cassandra Cluster

I use the Cassandra database cluster system to manage a new set of websites and once in a while I start getting many errors and the website stops working altogether.

When that happens, it is likely that Cassandra broke something in the temporary tables that it holds. The only way to go past that problem is to clear those tables. Until then, it will fail over and over again (they really would need some euristic to auto-clean up even if it means that you're losing some data.)

The command to repair the database, really quick, is as follow:

nodetool scrub snap_websites files

Note that ...

Why would Redirect and RedirectMatch in Apache2 not work?

As we are working on a new website, we had a problem where a redirect would not work. I tried both: a simple Redirect and a RedirectMatch as follow:

Redirect /
RedirectMatch permanent ^(.*)$$1

Both of these entries would not work at all.

I verified, to make sure, that the alias module was turned on. It was.

ls -l /var/apache2/mods-enabled

This did list the alias.conf and alias.load entries as expected.

So? What else?

Well... This was installed on a new server and we left the default entry in there:

ls -l ...

Useful online network tools

I'm starting this page and hope to think about it again at a later time when I find additional tools... but as I have network problems I often need these types of services to make sure I can get the information I need.

For more Network stuff, click on the Network tag!

What is your IP address?

Check your current IP address from your browser: [Super clean version!] [More advance and with ads...]

What is my DNS?

This one is for people who setup a DNS to make sure that it can accessed from all over the world. It ...

Hacking my NVG510 device

Earlz found a way to hack the NVG510 device and wrote a page about it: Rooting The NVG510 from the WebUI

He also offers a page that one can use to allow telnet connections to the NVG510 (by default it is locked up.) From there you can allow ssh and tftp connections too.

Note that this means if you are logged in your NVG510 and you click on a link on a bad server, you could actually allow remote connections from anyone! So that's a dangerous back door, although if you are not logged in the Web interface, then it is fine (assuming you do not then log in without thinking!?)

Just in case ...

Drupal paths that won't work!

As I created a new site to list all of my accounts on the Internet, I thought the folder where those accounts appear should be called profiles. But somehow autopath did not generate the URL Alias as expected.

I tried several times and each time it returned an empty alias. Then I tried adding the alias by hand and that was accepted by Drupal, but when I then tried to go to that page it failed with an Apache error which at first I found odd. Then I recalled that there was a folder named profiles in the top directory of Drupal. The Drupal code (from the

Wordpress Media Upload returns IO Error

I got a new word press website a couple days ago and got it installed in the last few days. There were 3 images missing so I started working on getting them in. When I got the first image, I went to Wordpress and I got an error... with no detailed explaination (maybe there is a log, but I don't know Wordpress that well to tell.)

The error message was just: IO Error

I was pretty sure that the problem was just that the folder where Wordpress tries to upload the new content was write protected from the Apache user. Under Ubuntu and Debian, the default name for that user is www-data and

Too many authentication failures for <username>

Today I tried to make use of sftp to transfer a website to Unfortunately, it kept giving me an error:

Received disconnect from <IP address>: 2: Too many authentication failures for <username>

I looked around why that would happen and could not really find anything decisive... until I found an issue in the trac system that uses. That issue mentioned the fact that the ssh-agent could be the culprit.

It was. Somehow the ssh-agent was sending key after key after key... exhausting the number of keys that will accept and thus made it

Restore Firefox warnings when viewing non-secure data on a secure page

One thing that I quickly do on my browsers is turn off warnings about non-secure data when browsing secure pages (with HTTPS .)

It's rarely a problem and with all those features you like to have (Facebook, Twitter, AddThis, ShareThis, Google Plus, and othe fun widgets...) it's hard to avoid. Actually, many times the problem lies in one of these scripts and thus you cannot just fix your website. Without that 3rd party script owner fixing their code, it just won't work at all.

Now, once in a while I work on a customer website and they really want to have a 100% clean slate. Thus,

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