68

In a VM on a cloud provider, I'm seeing a process with weird random name. It consumes significant network and CPU resources.

Here's how the process looks like from pstree view:

systemd(1)───eyshcjdmzg(37775)─┬─{eyshcjdmzg}(37782)
                               ├─{eyshcjdmzg}(37783)
                               └─{eyshcjdmzg}(37784)

I attached to the process using strace -p PID. Here's the output I've got: https://gist.github.com/gmile/eb34d262012afeea82af1c21713b1be9.

Killing the process does not work. It is somehow (via systemd?) resurrected. Here's how it looks from systemd point of view (note the weird IP address at the bottom):

$ systemctl status 37775
● session-60.scope - Session 60 of user root
   Loaded: loaded
Transient: yes
  Drop-In: /run/systemd/system/session-60.scope.d
           └─50-After-systemd-logind\x2eservice.conf, 50-After-systemd-user-sessions\x2eservice.conf, 50-Description.conf, 50-SendSIGHUP.conf, 50-Slice.conf, 50-TasksMax.conf
   Active: active (abandoned) since Tue 2018-03-06 10:42:51 EET; 1 day 1h ago
    Tasks: 14
   Memory: 155.4M
      CPU: 18h 56min 4.266s
   CGroup: /user.slice/user-0.slice/session-60.scope
           ├─37775 cat resolv.conf
           ├─48798 cd /etc
           ├─48799 sh
           ├─48804 who
           ├─48806 ifconfig eth0
           ├─48807 netstat -an
           ├─48825 cd /etc
           ├─48828 id
           ├─48831 ps -ef
           ├─48833 grep "A"
           └─48834 whoami

Mar 06 10:42:51 k8s-master systemd[1]: Started Session 60 of user root.
Mar 06 10:43:27 k8s-master sshd[37594]: Received disconnect from 23.27.74.92 port 59964:11:
Mar 06 10:43:27 k8s-master sshd[37594]: Disconnected from 23.27.74.92 port 59964
Mar 06 10:43:27 k8s-master sshd[37594]: pam_unix(sshd:session): session closed for user root

What is going on?!

  • 46
    The answer to "Is someone hacking me?" is always "Yes", the real question is "Has someone succeeded in hacking me?". – ChuckCottrill Mar 8 '18 at 1:46
  • 8
    the word is ‘cracking’ or ‘penetrating’, or ‘commandeering’, not necessarily ‘hacking’ – can-ned_food Mar 8 '18 at 17:50
  • 6
    @can-ned_food I was told that about 15 years ago. It took me a while to realize the distinction is a bunch of hogwash and "hacking" absolutely means the same thing. Even if that wasn't the case in 1980, language has certainly changed enough that it is now. – jpmc26 Mar 10 '18 at 0:01
  • @jpmc26 From what I understood, Hacking is the broader term: a hacker is also any ol' programmer who works at someone else's sloppy code. – can-ned_food Mar 10 '18 at 15:10
  • 1
    @can-ned_food It can be used that way, but it's much more commonly used to describe unauthorized access. It's nearly always clear from the context what is meant. – jpmc26 Mar 10 '18 at 15:19
137

eyshcjdmzg is a Linux DDoS trojan (easily found through a Google search). You've likely been hacked.

Take that server off-line now. It's not yours any longer.

Please read the following ServerFault Q/A carefully: How to deal with a compromised server.

Note that depending on who you are and where you are, you may additionally be legally obliged to report this incident to authorities. This is the case if you are working at a government agency in Sweden (e.g. a university), for example.

Related:

  • 2
    If you serve dutch customers also, and you store personal information(ip adresses, emails, names, shopping list, credit card info, passwords) you need to report it to datalekken.autoriteitpersoonsgegevens.nl/actionpage?0 – Tschallacka Mar 9 '18 at 9:48
  • @tschallacka surely IP address alone is not considered PII? Pretty much every Webserver anywhere stores IP addresses in it's access logs – Darren H Mar 10 '18 at 8:52
  • @DarrenH I'm assuming that it would cover "data that can be used to identify a person" etc. Logs are usually not seen as this type of data AFAIK, but it may be different if an IP address is explicitly stored in a database as part of an account record. – Kusalananda Mar 10 '18 at 8:54
  • That makes sense. Thanks for the clarification – Darren H Mar 10 '18 at 8:59
  • In the netherlands we are required to mask all octets before sending to google because the entire range falls under personal information, because it can be crosschecked with other records. A hacker could crosscheck with other logs to track your activities. So yes, its full persal information like an actual adress – Tschallacka Mar 10 '18 at 9:35
23

Yes. A google search for eyshcjdmzg indicates that your server has been compromised.

See How do I deal with a compromised server? for what to do about that (in short, wipe the system and re-install from scratch - you can't trust anything on it. I hope you have backups of important data and config files)

  • 18
    You'd think they'd bother to randomize the name on each infected system, but apparently not. – immibis Mar 7 '18 at 23:37
  • 2
    @immibis It may be an abbreviation, meaningful only to the authors. the DMZ bit is a real acronym. sh could mean "shell" and ey may be "eye" without the "e", but I'm just speculating. – Kusalananda Mar 8 '18 at 7:37
  • 13
    @Kusalananda I'd say "Eye without e Shell CJ Demilitarized zone g" trojan, not a bad name tho. – The-Vinh VO Mar 8 '18 at 9:10
  • 10
    @The-VinhVO Really rolls off the tongue – Dason Mar 8 '18 at 20:57

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