MESSAGE
DATE | 2015-11-16 |
FROM | Ruben Safir
|
SUBJECT | Re: [Hangout-NYLXS] ransomware - attacking apache
|
On 11/09/2015 08:24 AM, Ruben Safir wrote:
> On 11/09/2015 05:36 AM, Rick Moen wrote:
>> ou do not
>> happen to link to _LA Times_ articles, in my experience.
>
>
> I have from time to time because they have a good reporting on Israel.
> _______________________________________________
> hangout mailing list
> hangout-at-nylxs.com
> http://www.nylxs.com/
>
How to easily defeat Linux Encoder ransomware
For all the attention Linux.Encoder.1 ransomware has gotten, a lot of
people seem to be missing that it's easy to fix. Here's how to do it.
Steven J. Vaughan-Nichols
By Steven J. Vaughan-Nichols for Linux and Open Source | November 16,
2015 -- 12:45 GMT (04:45 PST) | Topic: Security
First things first. Linux.Encoder.1, the "Linux" crypto-ransomware, is
not a Linux security hole. This malware relies on a security hole in the
Magento web e-commerce platform, not Linux.
If you use Magento and haven't patched it since February 9, 2015 -- yes
it's been that long -- then, and only then, are you vulnerable.
Otherwise, your site can't possibly get Linux.Encoder.1.
The Magento attack resembles ransomware programs such as Windows'
CryptoWall and TorLocker. They encrypt your files and then demand
payment for the key to unlock your documents.
Let's say you do use Magento and you were foolish enough to leave an
e-commerce platform unpatched for over half a year. Patch it. Patch it now.
The ransomware guide: protection and eradication
If you're staring at your server in horror and far too many of your
files are encrypted by an attacker and your directories all have a file
entitled "README_FOR_DECRYPT.txt," congratulations, you've got it. It
appears that about 2,700 red-faced website administrators have
Linux.Encoder on their servers.
The good news is it's easy to get rid of.
You could, of course, pay the ransom fee of one Bitcoin, $325 at the
moment. I do not recommend you do this. Besides just encouraging
ransomware programmers, the crook's fix doesn't work well. Security
expert Brian Krebs reports that one system administrator who paid up,
got his files back but, the "decryption script that puts the data back
... somehow ... ate some characters in a few files, adding like a comma
or an extra space ... to the file."
So, I don't care how desperate you are, paying the ransom is a dumb move.
You can also have Dr. Web, the Russian security company, that discovered
Linux.Encoder, try to recover your files for you. This service is only
available to Dr. Web commercial programs subscribers. These programs are
Dr. Web Security Space or Dr. Web Enterprise Security Suite.
More security news
How to easily defeat Linux Encoder ransomware
Chrome zero-day flaw places millions of smartphone users at risk
Android Gmail app security hole lets you pretend to be anyone online
Encryption is not the enemy: A 21st century response to terror
Or, you can what I recommend, and just crack open your files yourself.
You see the would-be cyber-criminals made a fundamental mistake. Their
encryption method uses a faulty implementation of Advanced Encryption
Standard (AES) to generate the encryption key. Specifically, as the
anti-virus company Bitdefender reported, the "AES key is generated
locally on the victim's computer. ... rather than generating secure
random keys and IVs [initialization vector], the sample would derive
these two pieces of information from the libc rand() function seeded
with the current system time-stamp at the moment of encryption. This
information can be easily retrieved by looking at the file's time-stamp."
Armed with this, it's trivial -- well, for encryption experts -- to find
the key you need to restore your files. Since most of you don't know
your AES from your Playfair, Bitdefender is offering a free Python 2.7
script to obtain the Linux.Encoder key and IV for your containinated server.
Here's how to use it.
If you can boot your compromised server, download the script, and run it
as root . If you can't boot, download and decompress the file to a Linux
live USB stick. For this job, I recommend the SystemRescueCD Linux
distribution.
Then, mount the encrypted partition using the shell command :
mount /dev/[encrypted_partition]
Generate a list of encrypted files with the following command:
/mnt# sort_files.sh encrypted_partition > sorted_list
Issue a head command to get the first file:
/mnt# head -1 sorted_list
Run the decryption utility to get the encryption seed:
/mnt# python decrypter.py -f [first_file]
Decrypt all the other infected files using the displayed seed:
/mnt# python /tmp/new/decrypter.py -s [time-stamp.] -l sorted_list
Not comfortable with the Linux shell? Get someone who is a Linux expert
to help you.
Bitdefender is also, very generously, offering to help users with free
support from their web site. Go to the bottom of the page to find the form.
Finally, and always: Update your software always. If everyone had simply
done this that alone would have stopped Linux.Encoder in its tracks.
Related Stories:
_______________________________________________
hangout mailing list
hangout-at-nylxs.com
http://www.nylxs.com/
|
|