Distributed Bruteforce against SSH

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Distributed Bruteforce against SSH

by Gary Baribault-2 :: Rate this Message:

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I guess what I reported last week was the warmup round .. Where now
getting thousands of attemped logins with the standars dictionary of
potential login names.

As I stated, I'm not interested in avoiding these attacks, so please
don't sugges that I change the SSH port, my machines are safe enough ..

For those who missed it, I have three servers on the Internet, two cable
modems and one static and again, two of them are getting about 100
attacks per hour but instead of using Root for every attempt, we are now
seeing the standars alphabetical list of users.

What wories me is all of the Linux/Unix servers out there (and I guess
to a lesser degree Windows boxes with an SSH Daemon) that have many
normal remote users who are allowed remote access with SSH and have weak
passwords.

This attack seems to be aimed at them, and will certainly succeed.

See a sample of one of my logs below

Gary B

messages:May 11 21:59:39 salle sshd[5493]: Invalid user a'marie from
213.251.185.54
messages:May 11 21:59:39 salle sshd[5493]: Failed
keyboard-interactive/pam for invalid user a'marie from 213.251.185.54
port 33943 ssh2
messages:May 11 22:01:34 salle sshd[5519]: Invalid user aaliyah from
62.206.228.188
messages:May 11 22:01:34 salle sshd[5519]: Failed
keyboard-interactive/pam for invalid user aaliyah from 62.206.228.188
port 49207 ssh2
messages:May 11 22:03:11 salle sshd[5524]: Invalid user aaralyn from
212.220.166.26
messages:May 11 22:03:11 salle sshd[5524]: Failed
keyboard-interactive/pam for invalid user aaralyn from 212.220.166.26
port 1408 ssh2
messages:May 11 22:04:05 salle sshd[5528]: Invalid user aaron from
83.151.29.86
messages:May 11 22:04:05 salle sshd[5528]: Failed
keyboard-interactive/pam for invalid user aaron from 83.151.29.86 port
55756 ssh2
messages:May 11 22:05:34 salle sshd[5533]: Invalid user abbie from
70.43.165.34
messages:May 11 22:05:34 salle sshd[5533]: Failed
keyboard-interactive/pam for invalid user abbie from 70.43.165.34 port
48681 ssh2
messages:May 11 22:06:41 salle sshd[5537]: Invalid user abbott from
194.204.62.2
messages:May 11 22:06:41 salle sshd[5537]: Failed
keyboard-interactive/pam for invalid user abbott from 194.204.62.2 port
7799 ssh2
messages:May 11 22:08:33 salle sshd[5543]: Invalid user abdukrahman from
62.206.22.124
messages:May 11 22:08:34 salle sshd[5543]: Failed
keyboard-interactive/pam for invalid user abdukrahman from 62.206.22.124
port 50525 ssh2
messages:May 11 22:12:11 salle sshd[5558]: Invalid user abdulrahman from
196.211.191.58
messages:May 11 22:12:12 salle sshd[5558]: Failed
keyboard-interactive/pam for invalid user abdulrahman from
196.211.191.58 port 58081 ssh2
messages:May 11 22:12:55 salle sshd[5562]: Invalid user abe from
217.172.164.130
messages:May 11 22:12:55 salle sshd[5562]: Failed
keyboard-interactive/pam for invalid user abe from 217.172.164.130 port
56462 ssh2
messages:May 11 22:13:53 salle sshd[5566]: Invalid user abel from
80.68.94.169
messages:May 11 22:13:54 salle sshd[5566]: Failed
keyboard-interactive/pam for invalid user abel from 80.68.94.169 port
2229 ssh2
messages:May 11 22:15:47 salle sshd[5592]: Invalid user abia from
86.49.7.207
messages:May 11 22:15:47 salle sshd[5592]: Failed
keyboard-interactive/pam for invalid user abia from 86.49.7.207 port
1407 ssh2
messages:May 11 22:16:32 salle sshd[5595]: Invalid user abiba from
200.117.122.206
messages:May 11 22:16:33 salle sshd[5595]: Failed
keyboard-interactive/pam for invalid user abiba from 200.117.122.206
port 53258 ssh2
messages:May 11 22:18:02 salle sshd[5599]: Invalid user abie from
208.189.14.194
messages:May 11 22:18:02 salle sshd[5599]: Failed
keyboard-interactive/pam for invalid user abie from 208.189.14.194 port
36420 ssh2
messages:May 11 22:18:24 salle sshd[5602]: Invalid user abigail from
69.128.70.86
messages:May 11 22:18:25 salle sshd[5602]: Failed
keyboard-interactive/pam for invalid user abigail from 69.128.70.86 port
3154 ssh2
messages:May 11 22:19:53 salle sshd[5605]: Invalid user abner from
62.147.203.49
messages:May 11 22:19:53 salle sshd[5605]: Failed
keyboard-interactive/pam for invalid user abner from 62.147.203.49 port
38321 ssh2
messages:May 11 22:20:17 salle sshd[5608]: Invalid user abra from
61.29.122.140
messages:May 11 22:20:17 salle sshd[5609]: input_userauth_request:
invalid user abra
messages:May 11 22:20:17 salle sshd[5608]: Failed
keyboard-interactive/pam for invalid user abra from 61.29.122.140 port
53367 ssh2
messages:May 11 22:20:57 salle sshd[5612]: Invalid user abra from
200.166.58.108
messages:May 11 22:20:58 salle sshd[5612]: Failed
keyboard-interactive/pam for invalid user abra from 200.166.58.108 port
41499 ssh2
messages:May 11 22:21:28 salle sshd[5615]: Invalid user abraham from
82.193.22.18
messages:May 11 22:21:28 salle sshd[5616]: input_userauth_request:
invalid user abraham
messages:May 11 22:21:28 salle sshd[5615]: Failed
keyboard-interactive/pam for invalid user abraham from 82.193.22.18 port
33116 ssh2
messages:May 11 22:22:36 salle sshd[5619]: Invalid user abram from
66.159.198.155
messages:May 11 22:22:37 salle sshd[5619]: Failed
keyboard-interactive/pam for invalid user abram from 66.159.198.155 port
45869 ssh2
messages:May 11 22:22:53 salle sshd[5622]: Invalid user abram from
89.110.144.212
messages:May 11 22:22:53 salle sshd[5623]: input_userauth_request:
invalid user abram
messages:May 11 22:22:53 salle sshd[5622]: Failed
keyboard-interactive/pam for invalid user abram from 89.110.144.212 port
35527 ssh2
messages:May 11 22:23:29 salle sshd[5625]: Invalid user abrianna from
204.13.164.75
messages:May 11 22:23:29 salle sshd[5625]: Failed
keyboard-interactive/pam for invalid user abrianna from 204.13.164.75
port 36896 ssh2
messages:May 11 22:24:22 salle sshd[5629]: Invalid user abrienda from
87.234.200.80
messages:May 11 22:24:22 salle sshd[5629]: Failed
keyboard-interactive/pam for invalid user abrienda from 87.234.200.80
port 17603 ssh2
messages:May 11 22:25:04 salle sshd[5632]: Invalid user abrienda from
168.234.199.84
messages:May 11 22:25:04 salle sshd[5632]: Failed
keyboard-interactive/pam for invalid user abrienda from 168.234.199.84
port 47504 ssh2
messages:May 11 22:25:52 salle sshd[5635]: Invalid user abril from
83.246.96.70
messages:May 11 22:25:52 salle sshd[5635]: Failed
keyboard-interactive/pam for invalid user abril from 83.246.96.70 port
48594 ssh2
messages:May 11 22:25:55 salle sshd[5638]: Invalid user abril from
62.2.99.174
messages:May 11 22:25:56 salle sshd[5638]: Failed
keyboard-interactive/pam for invalid user abril from 62.2.99.174 port
1424 ssh2
messages:May 11 22:27:00 salle sshd[5642]: Invalid user absolom from
200.117.122.206
messages:May 11 22:27:01 salle sshd[5642]: Failed
keyboard-interactive/pam for invalid user absolom from 200.117.122.206
port 45918 ssh2
messages:May 11 22:27:15 salle sshd[5645]: Invalid user abu from
85.14.219.67
messages:May 11 22:27:15 salle sshd[5645]: Failed
keyboard-interactive/pam for invalid user abu from 85.14.219.67 port
38085 ssh2
messages:May 11 22:28:48 salle sshd[5649]: Invalid user acacia from
64.83.58.161
messages:May 11 22:28:48 salle sshd[5649]: Failed
keyboard-interactive/pam for invalid user acacia from 64.83.58.161 port
39750 ssh2
messages:May 11 22:30:48 salle sshd[5675]: Invalid user ace from
61.29.122.140
messages:May 11 22:30:48 salle sshd[5676]: input_userauth_request:
invalid user ace
messages:May 11 22:30:48 salle sshd[5675]: Failed
keyboard-interactive/pam for invalid user ace from 61.29.122.140 port
60660 ssh2
messages:May 11 22:32:25 salle sshd[5680]: Invalid user acton from
217.98.80.5
messages:May 11 22:32:25 salle sshd[5680]: Failed
keyboard-interactive/pam for invalid user acton from 217.98.80.5 port
10497 ssh2
messages:May 11 22:32:57 salle sshd[5683]: Invalid user acton from
88.198.47.143
messages:May 11 22:32:57 salle sshd[5683]: Failed
keyboard-interactive/pam for invalid user acton from 88.198.47.143 port
39369 ssh2
messages:May 11 22:33:21 salle sshd[5686]: Invalid user ada from
200.74.136.246
messages:May 11 22:33:21 salle sshd[5686]: Failed
keyboard-interactive/pam for invalid user ada from 200.74.136.246 port
35651 ssh2
messages:May 11 22:33:51 salle sshd[5689]: Invalid user ada from
69.15.102.215
messages:May 11 22:33:51 salle sshd[5689]: Failed
keyboard-interactive/pam for invalid user ada from 69.15.102.215 port
50657 ssh2
messages:May 11 22:34:57 salle sshd[5693]: Invalid user adah from
216.197.204.76
messages:May 11 22:34:57 salle sshd[5693]: Failed
keyboard-interactive/pam for invalid user adah from 216.197.204.76 port
43581 ssh2
messages:May 11 22:35:17 salle sshd[5696]: Invalid user adair from
76.160.167.251
messages:May 11 22:35:17 salle sshd[5696]: Failed
keyboard-interactive/pam for invalid user adair from 76.160.167.251 port
50495 ssh2
messages:May 11 22:38:36 salle sshd[5715]: Invalid user adamina from
201.21.210.151
messages:May 11 22:38:36 salle sshd[5716]: input_userauth_request:
invalid user adamina
messages:May 11 22:38:37 salle sshd[5715]: Failed
keyboard-interactive/pam for invalid user adamina from 201.21.210.151
port 34881 ssh2
messages:May 11 22:38:54 salle sshd[5718]: Invalid user adamina from
133.6.61.76
messages:May 11 22:38:54 salle sshd[5718]: Failed
keyboard-interactive/pam for invalid user adamina from 133.6.61.76 port
44428 ssh2
messages:May 11 22:39:29 salle sshd[5721]: Invalid user adamma from
212.51.52.244
messages:May 11 22:39:29 salle sshd[5721]: Failed
keyboard-interactive/pam for invalid user adamma from 212.51.52.244 port
41180 ssh2
messages:May 11 22:39:51 salle sshd[5724]: Invalid user adamma from
83.244.156.204
messages:May 11 22:39:51 salle sshd[5724]: Failed
keyboard-interactive/pam for invalid user adamma from 83.244.156.204
port 50954 ssh2
messages:May 11 22:41:02 salle sshd[5735]: Invalid user adara from
88.198.47.143
messages:May 11 22:41:02 salle sshd[5735]: Failed
keyboard-interactive/pam for invalid user adara from 88.198.47.143 port
33031 ssh2
messages:May 11 22:42:28 salle sshd[5738]: Invalid user addison from
62.2.211.46
messages:May 11 22:42:28 salle sshd[5738]: Failed
keyboard-interactive/pam for invalid user addison from 62.2.211.46 port
29580 ssh2





RE: Distributed Bruteforce against SSH

by Keith T. Morgan :: Rate this Message:

Reply to Author | View Threaded | Show Only this Message

Yep.  I've been seeing them too.  What's interesting is that the botnet is sharing "state" information regarding where the collective botnet is in the dictionary.  This will completely bypass fail2ban since each subsequent dictionary word is tried from a different host.

I experimented a bit by blocking huge swaths of the internet at the firewall, and watching.  For example, I dropped everything inbound except for 66.0.0.0/8, 67.0.0.0/8 and 68.0.0.0/8.  Sure enough, eventually, the next attempt came through.  And it used the next sequential username in the dictionary (as captured on a logically nearby host).

When I opened things up again, the dictionary attack simply sped up, in the proper word sequence, coming from more hosts.


> -----Original Message-----
> From: Gary Baribault [mailto:gary@...]
> Sent: Monday, May 12, 2008 11:28 AM
> To: incidents@...
> Subject: Distributed Bruteforce against SSH
>
>
> I guess what I reported last week was the warmup round ..
> Where now getting thousands of attemped logins with the
> standars dictionary of potential login names.
>
> As I stated, I'm not interested in avoiding these attacks, so
> please don't sugges that I change the SSH port, my machines
> are safe enough ..
>
> For those who missed it, I have three servers on the
> Internet, two cable modems and one static and again, two of
> them are getting about 100 attacks per hour but instead of
> using Root for every attempt, we are now seeing the standars
> alphabetical list of users.
>
> What wories me is all of the Linux/Unix servers out there
> (and I guess to a lesser degree Windows boxes with an SSH
> Daemon) that have many normal remote users who are allowed
> remote access with SSH and have weak passwords.
>
> This attack seems to be aimed at them, and will certainly succeed.
>
> See a sample of one of my logs below
>
> Gary B
>
> messages:May 11 21:59:39 salle sshd[5493]: Invalid user
> a'marie from 213.251.185.54 messages:May 11 21:59:39 salle
> sshd[5493]: Failed keyboard-interactive/pam for invalid user
> a'marie from 213.251.185.54 port 33943 ssh2 messages:May 11
> 22:01:34 salle sshd[5519]: Invalid user aaliyah from
> 62.206.228.188 messages:May 11 22:01:34 salle sshd[5519]:
> Failed keyboard-interactive/pam for invalid user aaliyah from
> 62.206.228.188 port 49207 ssh2 messages:May 11 22:03:11 salle
> sshd[5524]: Invalid user aaralyn from 212.220.166.26
> messages:May 11 22:03:11 salle sshd[5524]: Failed
> keyboard-interactive/pam for invalid user aaralyn from
> 212.220.166.26 port 1408 ssh2 messages:May 11 22:04:05 salle
> sshd[5528]: Invalid user aaron from 83.151.29.86 messages:May
> 11 22:04:05 salle sshd[5528]: Failed keyboard-interactive/pam
> for invalid user aaron from 83.151.29.86 port 55756 ssh2
> messages:May 11 22:05:34 salle sshd[5533]: Invalid user abbie
> from 70.43.165.34 messages:May 11 22:05:34 salle sshd[5533]:
> Failed keyboard-interactive/pam for invalid user abbie from
> 70.43.165.34 port 48681 ssh2 messages:May 11 22:06:41 salle
> sshd[5537]: Invalid user abbott from 194.204.62.2
> messages:May 11 22:06:41 salle sshd[5537]: Failed
> keyboard-interactive/pam for invalid user abbott from
> 194.204.62.2 port 7799 ssh2 messages:May 11 22:08:33 salle
> sshd[5543]: Invalid user abdukrahman from 62.206.22.124
> messages:May 11 22:08:34 salle sshd[5543]: Failed
> keyboard-interactive/pam for invalid user abdukrahman from
> 62.206.22.124 port 50525 ssh2 messages:May 11 22:12:11 salle
> sshd[5558]: Invalid user abdulrahman from 196.211.191.58
> messages:May 11 22:12:12 salle sshd[5558]: Failed
> keyboard-interactive/pam for invalid user abdulrahman from
> 196.211.191.58 port 58081 ssh2 messages:May 11 22:12:55 salle
> sshd[5562]: Invalid user abe from 217.172.164.130
> messages:May 11 22:12:55 salle sshd[5562]: Failed
> keyboard-interactive/pam for invalid user abe from
> 217.172.164.130 port 56462 ssh2 messages:May 11 22:13:53
> salle sshd[5566]: Invalid user abel from 80.68.94.169
> messages:May 11 22:13:54 salle sshd[5566]: Failed
> keyboard-interactive/pam for invalid user abel from
> 80.68.94.169 port 2229 ssh2 messages:May 11 22:15:47 salle
> sshd[5592]: Invalid user abia from 86.49.7.207 messages:May
> 11 22:15:47 salle sshd[5592]: Failed keyboard-interactive/pam
> for invalid user abia from 86.49.7.207 port 1407 ssh2
> messages:May 11 22:16:32 salle sshd[5595]: Invalid user abiba
> from 200.117.122.206 messages:May 11 22:16:33 salle
> sshd[5595]: Failed keyboard-interactive/pam for invalid user
> abiba from 200.117.122.206 port 53258 ssh2 messages:May 11
> 22:18:02 salle sshd[5599]: Invalid user abie from
> 208.189.14.194 messages:May 11 22:18:02 salle sshd[5599]:
> Failed keyboard-interactive/pam for invalid user abie from
> 208.189.14.194 port 36420 ssh2 messages:May 11 22:18:24 salle
> sshd[5602]: Invalid user abigail from 69.128.70.86
> messages:May 11 22:18:25 salle sshd[5602]: Failed
> keyboard-interactive/pam for invalid user abigail from
> 69.128.70.86 port 3154 ssh2 messages:May 11 22:19:53 salle
> sshd[5605]: Invalid user abner from 62.147.203.49
> messages:May 11 22:19:53 salle sshd[5605]: Failed
> keyboard-interactive/pam for invalid user abner from
> 62.147.203.49 port 38321 ssh2 messages:May 11 22:20:17 salle
> sshd[5608]: Invalid user abra from 61.29.122.140 messages:May
> 11 22:20:17 salle sshd[5609]: input_userauth_request: invalid
> user abra messages:May 11 22:20:17 salle sshd[5608]: Failed
> keyboard-interactive/pam for invalid user abra from
> 61.29.122.140 port 53367 ssh2 messages:May 11 22:20:57 salle
> sshd[5612]: Invalid user abra from 200.166.58.108
> messages:May 11 22:20:58 salle sshd[5612]: Failed
> keyboard-interactive/pam for invalid user abra from
> 200.166.58.108 port 41499 ssh2 messages:May 11 22:21:28 salle
> sshd[5615]: Invalid user abraham from 82.193.22.18
> messages:May 11 22:21:28 salle sshd[5616]:
> input_userauth_request: invalid user abraham messages:May 11
> 22:21:28 salle sshd[5615]: Failed keyboard-interactive/pam
> for invalid user abraham from 82.193.22.18 port 33116 ssh2
> messages:May 11 22:22:36 salle sshd[5619]: Invalid user abram
> from 66.159.198.155 messages:May 11 22:22:37 salle
> sshd[5619]: Failed keyboard-interactive/pam for invalid user
> abram from 66.159.198.155 port 45869 ssh2 messages:May 11
> 22:22:53 salle sshd[5622]: Invalid user abram from
> 89.110.144.212 messages:May 11 22:22:53 salle sshd[5623]:
> input_userauth_request: invalid user abram messages:May 11
> 22:22:53 salle sshd[5622]: Failed keyboard-interactive/pam
> for invalid user abram from 89.110.144.212 port 35527 ssh2
> messages:May 11 22:23:29 salle sshd[5625]: Invalid user
> abrianna from 204.13.164.75 messages:May 11 22:23:29 salle
> sshd[5625]: Failed keyboard-interactive/pam for invalid user
> abrianna from 204.13.164.75 port 36896 ssh2 messages:May 11
> 22:24:22 salle sshd[5629]: Invalid user abrienda from
> 87.234.200.80 messages:May 11 22:24:22 salle sshd[5629]:
> Failed keyboard-interactive/pam for invalid user abrienda
> from 87.234.200.80 port 17603 ssh2 messages:May 11 22:25:04
> salle sshd[5632]: Invalid user abrienda from 168.234.199.84
> messages:May 11 22:25:04 salle sshd[5632]: Failed
> keyboard-interactive/pam for invalid user abrienda from
> 168.234.199.84 port 47504 ssh2 messages:May 11 22:25:52 salle
> sshd[5635]: Invalid user abril from 83.246.96.70 messages:May
> 11 22:25:52 salle sshd[5635]: Failed keyboard-interactive/pam
> for invalid user abril from 83.246.96.70 port 48594 ssh2
> messages:May 11 22:25:55 salle sshd[5638]: Invalid user abril
> from 62.2.99.174 messages:May 11 22:25:56 salle sshd[5638]:
> Failed keyboard-interactive/pam for invalid user abril from
> 62.2.99.174 port 1424 ssh2 messages:May 11 22:27:00 salle
> sshd[5642]: Invalid user absolom from 200.117.122.206
> messages:May 11 22:27:01 salle sshd[5642]: Failed
> keyboard-interactive/pam for invalid user absolom from
> 200.117.122.206 port 45918 ssh2 messages:May 11 22:27:15
> salle sshd[5645]: Invalid user abu from 85.14.219.67
> messages:May 11 22:27:15 salle sshd[5645]: Failed
> keyboard-interactive/pam for invalid user abu from
> 85.14.219.67 port 38085 ssh2 messages:May 11 22:28:48 salle
> sshd[5649]: Invalid user acacia from 64.83.58.161
> messages:May 11 22:28:48 salle sshd[5649]: Failed
> keyboard-interactive/pam for invalid user acacia from
> 64.83.58.161 port 39750 ssh2 messages:May 11 22:30:48 salle
> sshd[5675]: Invalid user ace from 61.29.122.140 messages:May
> 11 22:30:48 salle sshd[5676]: input_userauth_request: invalid
> user ace messages:May 11 22:30:48 salle sshd[5675]: Failed
> keyboard-interactive/pam for invalid user ace from
> 61.29.122.140 port 60660 ssh2 messages:May 11 22:32:25 salle
> sshd[5680]: Invalid user acton from 217.98.80.5 messages:May
> 11 22:32:25 salle sshd[5680]: Failed keyboard-interactive/pam
> for invalid user acton from 217.98.80.5 port 10497 ssh2
> messages:May 11 22:32:57 salle sshd[5683]: Invalid user acton
> from 88.198.47.143 messages:May 11 22:32:57 salle sshd[5683]:
> Failed keyboard-interactive/pam for invalid user acton from
> 88.198.47.143 port 39369 ssh2 messages:May 11 22:33:21 salle
> sshd[5686]: Invalid user ada from 200.74.136.246 messages:May
> 11 22:33:21 salle sshd[5686]: Failed keyboard-interactive/pam
> for invalid user ada from 200.74.136.246 port 35651 ssh2
> messages:May 11 22:33:51 salle sshd[5689]: Invalid user ada
> from 69.15.102.215 messages:May 11 22:33:51 salle sshd[5689]:
> Failed keyboard-interactive/pam for invalid user ada from
> 69.15.102.215 port 50657 ssh2 messages:May 11 22:34:57 salle
> sshd[5693]: Invalid user adah from 216.197.204.76
> messages:May 11 22:34:57 salle sshd[5693]: Failed
> keyboard-interactive/pam for invalid user adah from
> 216.197.204.76 port 43581 ssh2 messages:May 11 22:35:17 salle
> sshd[5696]: Invalid user adair from 76.160.167.251
> messages:May 11 22:35:17 salle sshd[5696]: Failed
> keyboard-interactive/pam for invalid user adair from
> 76.160.167.251 port 50495 ssh2 messages:May 11 22:38:36 salle
> sshd[5715]: Invalid user adamina from 201.21.210.151
> messages:May 11 22:38:36 salle sshd[5716]:
> input_userauth_request: invalid user adamina messages:May 11
> 22:38:37 salle sshd[5715]: Failed keyboard-interactive/pam
> for invalid user adamina from 201.21.210.151 port 34881 ssh2
> messages:May 11 22:38:54 salle sshd[5718]: Invalid user
> adamina from 133.6.61.76 messages:May 11 22:38:54 salle
> sshd[5718]: Failed keyboard-interactive/pam for invalid user
> adamina from 133.6.61.76 port 44428 ssh2 messages:May 11
> 22:39:29 salle sshd[5721]: Invalid user adamma from
> 212.51.52.244 messages:May 11 22:39:29 salle sshd[5721]:
> Failed keyboard-interactive/pam for invalid user adamma from
> 212.51.52.244 port 41180 ssh2 messages:May 11 22:39:51 salle
> sshd[5724]: Invalid user adamma from 83.244.156.204
> messages:May 11 22:39:51 salle sshd[5724]: Failed
> keyboard-interactive/pam for invalid user adamma from
> 83.244.156.204 port 50954 ssh2 messages:May 11 22:41:02 salle
> sshd[5735]: Invalid user adara from 88.198.47.143
> messages:May 11 22:41:02 salle sshd[5735]: Failed
> keyboard-interactive/pam for invalid user adara from
> 88.198.47.143 port 33031 ssh2 messages:May 11 22:42:28 salle
> sshd[5738]: Invalid user addison from 62.2.211.46
> messages:May 11 22:42:28 salle sshd[5738]: Failed
> keyboard-interactive/pam for invalid user addison from
> 62.2.211.46 port 29580 ssh2
>
>
>
>
>

RE: Distributed Bruteforce against SSH

by Keith T. Morgan :: Rate this Message:

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I wanted to follow up on this after putting a little more thought into it.  Honestly, I'm quite impressed by the intelligence the botnet is exhibiting.  Based on the testing I've done, it's clear that the entire botnet is collectively sharing its position in the dictionary on a per-target basis.  Fairly slick, IMO.

> -----Original Message-----
> From: Gary Baribault [mailto:gary@...]
> Sent: Monday, May 12, 2008 11:28 AM
> To: incidents@...
> Subject: Distributed Bruteforce against SSH
>
>
> I guess what I reported last week was the warmup round ..
> Where now getting thousands of attemped logins with the
> standars dictionary of potential login names.
>

Re: Distributed Bruteforce against SSH

by Tim Kennedy :: Rate this Message:

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On Mon, May 12, 2008 at 2:01 PM, Keith T. Morgan
<keith.morgan@...> wrote:
> I wanted to follow up on this after putting a little more thought into it.  Honestly, I'm quite impressed by the intelligence the botnet is exhibiting.  Based on the testing I've done, it's clear that the entire botnet is collectively sharing its position in the dictionary on a per-target basis.  Fairly slick, IMO.

Agreed.

If you're concerned, start requiring ssh-keys for authentication.  If
you use RedHat (or derivatives thereof) and have the pam_succeed_if
PAM module available, you can at the very least make sure that any
non-authorized user accounts (even if they actually exist, and have a
password) can't log in via ssh.    Like users who only get email
privileges, or who only have ftp privs to update a website.

Mitigation is the name of the game, since the botnets tend to span
large areas of the IP space, blocking entire networks risks making
your servers/services unusable.

-Tim

Parent Message unknown Re: Distributed Bruteforce against SSH

by Gary Baribault-2 :: Rate this Message:

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Yep, that's what I use, and that's what the distributed atack is all
about, since the same IP is not always used, then the DenyHost script
dows not kick in .. I actually get about 30 DenyHost messages per hour,
so there is some re-use of IPs happening, but not that many.

Gary B




Joel Esler wrote:
>  Have you looked into a tool called "denyhosts"?
>
>  J
>
>  On May 12, 2008, at 11:27 AM, Gary Baribault wrote:
>
> > I guess what I reported last week was the warmup round .. Where now
getting thousands of attemped logins with the standars dictionary of
potential login names.
> >
> > As I stated, I'm not interested in avoiding these attacks, so please
don't sugges that I change the SSH port, my machines are safe enough ..
> >
> > For those who missed it, I have three servers on the Internet, two
cable modems and one static and again, two of them are getting about 100
attacks per hour but instead of using Root for every attempt, we are now
seeing the standars alphabetical list of users.
> >
> > What wories me is all of the Linux/Unix servers out there (and I
guess to a lesser degree Windows boxes with an SSH Daemon) that have
many normal remote users who are allowed remote access with SSH and have
weak passwords.
> >
> > This attack seems to be aimed at them, and will certainly succeed.
> >
> > See a sample of one of my logs below
> >
> > Gary B
> >
> > messages:May 11 21:59:39 salle sshd[5493]: Invalid user a'marie from
213.251.185.54
> > messages:May 11 21:59:39 salle sshd[5493]: Failed
keyboard-interactive/pam for invalid user a'marie from 213.251.185.54
port 33943 ssh2
> > messages:May 11 22:01:34 salle sshd[5519]: Invalid user aaliyah from
62.206.228.188
> > messages:May 11 22:01:34 salle sshd[5519]: Failed
keyboard-interactive/pam for invalid user aaliyah from 62.206.228.188
port 49207 ssh2
> > messages:May 11 22:03:11 salle sshd[5524]: Invalid user aaralyn from
212.220.166.26
> > messages:May 11 22:03:11 salle sshd[5524]: Failed
keyboard-interactive/pam for invalid user aaralyn from 212.220.166.26
port 1408 ssh2
> > messages:May 11 22:04:05 salle sshd[5528]: Invalid user aaron from
83.151.29.86
> > messages:May 11 22:04:05 salle sshd[5528]: Failed
keyboard-interactive/pam for invalid user aaron from 83.151.29.86 port
55756 ssh2
> > messages:May 11 22:05:34 salle sshd[5533]: Invalid user abbie from
70.43.165.34
> > messages:May 11 22:05:34 salle sshd[5533]: Failed
keyboard-interactive/pam for invalid user abbie from 70.43.165.34 port
48681 ssh2
> > messages:May 11 22:06:41 salle sshd[5537]: Invalid user abbott from
194.204.62.2
> > messages:May 11 22:06:41 salle sshd[5537]: Failed
keyboard-interactive/pam for invalid user abbott from 194.204.62.2 port
7799 ssh2
> > messages:May 11 22:08:33 salle sshd[5543]: Invalid user abdukrahman
from 62.206.22.124
> > messages:May 11 22:08:34 salle sshd[5543]: Failed
keyboard-interactive/pam for invalid user abdukrahman from 62.206.22.124
port 50525 ssh2
> > messages:May 11 22:12:11 salle sshd[5558]: Invalid user abdulrahman
from 196.211.191.58
> > messages:May 11 22:12:12 salle sshd[5558]: Failed
keyboard-interactive/pam for invalid user abdulrahman from
196.211.191.58 port 58081 ssh2
> > messages:May 11 22:12:55 salle sshd[5562]: Invalid user abe from
217.172.164.130
> > messages:May 11 22:12:55 salle sshd[5562]: Failed
keyboard-interactive/pam for invalid user abe from 217.172.164.130 port
56462 ssh2
> > messages:May 11 22:13:53 salle sshd[5566]: Invalid user abel from
80.68.94.169
> > messages:May 11 22:13:54 salle sshd[5566]: Failed
keyboard-interactive/pam for invalid user abel from 80.68.94.169 port
2229 ssh2
> > messages:May 11 22:15:47 salle sshd[5592]: Invalid user abia from
86.49.7.207
> > messages:May 11 22:15:47 salle sshd[5592]: Failed
keyboard-interactive/pam for invalid user abia from 86.49.7.207 port
1407 ssh2
> > messages:May 11 22:16:32 salle sshd[5595]: Invalid user abiba from
200.117.122.206
> > messages:May 11 22:16:33 salle sshd[5595]: Failed
keyboard-interactive/pam for invalid user abiba from 200.117.122.206
port 53258 ssh2
> > messages:May 11 22:18:02 salle sshd[5599]: Invalid user abie from
208.189.14.194
> > messages:May 11 22:18:02 salle sshd[5599]: Failed
keyboard-interactive/pam for invalid user abie from 208.189.14.194 port
36420 ssh2
> > messages:May 11 22:18:24 salle sshd[5602]: Invalid user abigail from
69.128.70.86
> > messages:May 11 22:18:25 salle sshd[5602]: Failed
keyboard-interactive/pam for invalid user abigail from 69.128.70.86 port
3154 ssh2
> > messages:May 11 22:19:53 salle sshd[5605]: Invalid user abner from
62.147.203.49
> > messages:May 11 22:19:53 salle sshd[5605]: Failed
keyboard-interactive/pam for invalid user abner from 62.147.203.49 port
38321 ssh2
> > messages:May 11 22:20:17 salle sshd[5608]: Invalid user abra from
61.29.122.140
> > messages:May 11 22:20:17 salle sshd[5609]: input_userauth_request:
invalid user abra
> > messages:May 11 22:20:17 salle sshd[5608]: Failed
keyboard-interactive/pam for invalid user abra from 61.29.122.140 port
53367 ssh2
> > messages:May 11 22:20:57 salle sshd[5612]: Invalid user abra from
200.166.58.108
> > messages:May 11 22:20:58 salle sshd[5612]: Failed
keyboard-interactive/pam for invalid user abra from 200.166.58.108 port
41499 ssh2
> > messages:May 11 22:21:28 salle sshd[5615]: Invalid user abraham from
82.193.22.18
> > messages:May 11 22:21:28 salle sshd[5616]: input_userauth_request:
invalid user abraham
> > messages:May 11 22:21:28 salle sshd[5615]: Failed
keyboard-interactive/pam for invalid user abraham from 82.193.22.18 port
33116 ssh2
> > messages:May 11 22:22:36 salle sshd[5619]: Invalid user abram from
66.159.198.155
> > messages:May 11 22:22:37 salle sshd[5619]: Failed
keyboard-interactive/pam for invalid user abram from 66.159.198.155 port
45869 ssh2
> > messages:May 11 22:22:53 salle sshd[5622]: Invalid user abram from
89.110.144.212
> > messages:May 11 22:22:53 salle sshd[5623]: input_userauth_request:
invalid user abram
> > messages:May 11 22:22:53 salle sshd[5622]: Failed
keyboard-interactive/pam for invalid user abram from 89.110.144.212 port
35527 ssh2
> > messages:May 11 22:23:29 salle sshd[5625]: Invalid user abrianna from
204.13.164.75
> > messages:May 11 22:23:29 salle sshd[5625]: Failed
keyboard-interactive/pam for invalid user abrianna from 204.13.164.75
port 36896 ssh2
> > messages:May 11 22:24:22 salle sshd[5629]: Invalid user abrienda from
87.234.200.80
> > messages:May 11 22:24:22 salle sshd[5629]: Failed
keyboard-interactive/pam for invalid user abrienda from 87.234.200.80
port 17603 ssh2
> > messages:May 11 22:25:04 salle sshd[5632]: Invalid user abrienda from
168.234.199.84
> > messages:May 11 22:25:04 salle sshd[5632]: Failed
keyboard-interactive/pam for invalid user abrienda from 168.234.199.84
port 47504 ssh2
> > messages:May 11 22:25:52 salle sshd[5635]: Invalid user abril from
83.246.96.70
> > messages:May 11 22:25:52 salle sshd[5635]: Failed
keyboard-interactive/pam for invalid user abril from 83.246.96.70 port
48594 ssh2
> > messages:May 11 22:25:55 salle sshd[5638]: Invalid user abril from
62.2.99.174
> > messages:May 11 22:25:56 salle sshd[5638]: Failed
keyboard-interactive/pam for invalid user abril from 62.2.99.174 port
1424 ssh2
> > messages:May 11 22:27:00 salle sshd[5642]: Invalid user absolom from
200.117.122.206
> > messages:May 11 22:27:01 salle sshd[5642]: Failed
keyboard-interactive/pam for invalid user absolom from 200.117.122.206
port 45918 ssh2
> > messages:May 11 22:27:15 salle sshd[5645]: Invalid user abu from
85.14.219.67
> > messages:May 11 22:27:15 salle sshd[5645]: Failed
keyboard-interactive/pam for invalid user abu from 85.14.219.67 port
38085 ssh2
> > messages:May 11 22:28:48 salle sshd[5649]: Invalid user acacia from
64.83.58.161
> > messages:May 11 22:28:48 salle sshd[5649]: Failed
keyboard-interactive/pam for invalid user acacia from 64.83.58.161 port
39750 ssh2
> > messages:May 11 22:30:48 salle sshd[5675]: Invalid user ace from
61.29.122.140
> > messages:May 11 22:30:48 salle sshd[5676]: input_userauth_request:
invalid user ace
> > messages:May 11 22:30:48 salle sshd[5675]: Failed
keyboard-interactive/pam for invalid user ace from 61.29.122.140 port
60660 ssh2
> > messages:May 11 22:32:25 salle sshd[5680]: Invalid user acton from
217.98.80.5
> > messages:May 11 22:32:25 salle sshd[5680]: Failed
keyboard-interactive/pam for invalid user acton from 217.98.80.5 port
10497 ssh2
> > messages:May 11 22:32:57 salle sshd[5683]: Invalid user acton from
88.198.47.143
> > messages:May 11 22:32:57 salle sshd[5683]: Failed
keyboard-interactive/pam for invalid user acton from 88.198.47.143 port
39369 ssh2
> > messages:May 11 22:33:21 salle sshd[5686]: Invalid user ada from
200.74.136.246
> > messages:May 11 22:33:21 salle sshd[5686]: Failed
keyboard-interactive/pam for invalid user ada from 200.74.136.246 port
35651 ssh2
> > messages:May 11 22:33:51 salle sshd[5689]: Invalid user ada from
69.15.102.215
> > messages:May 11 22:33:51 salle sshd[5689]: Failed
keyboard-interactive/pam for invalid user ada from 69.15.102.215 port
50657 ssh2
> > messages:May 11 22:34:57 salle sshd[5693]: Invalid user adah from
216.197.204.76
> > messages:May 11 22:34:57 salle sshd[5693]: Failed
keyboard-interactive/pam for invalid user adah from 216.197.204.76 port
43581 ssh2
> > messages:May 11 22:35:17 salle sshd[5696]: Invalid user adair from
76.160.167.251
> > messages:May 11 22:35:17 salle sshd[5696]: Failed
keyboard-interactive/pam for invalid user adair from 76.160.167.251 port
50495 ssh2
> > messages:May 11 22:38:36 salle sshd[5715]: Invalid user adamina from
201.21.210.151
> > messages:May 11 22:38:36 salle sshd[5716]: input_userauth_request:
invalid user adamina
> > messages:May 11 22:38:37 salle sshd[5715]: Failed
keyboard-interactive/pam for invalid user adamina from 201.21.210.151
port 34881 ssh2
> > messages:May 11 22:38:54 salle sshd[5718]: Invalid user adamina from
133.6.61.76
> > messages:May 11 22:38:54 salle sshd[5718]: Failed
keyboard-interactive/pam for invalid user adamina from 133.6.61.76 port
44428 ssh2
> > messages:May 11 22:39:29 salle sshd[5721]: Invalid user adamma from
212.51.52.244
> > messages:May 11 22:39:29 salle sshd[5721]: Failed
keyboard-interactive/pam for invalid user adamma from 212.51.52.244 port
41180 ssh2
> > messages:May 11 22:39:51 salle sshd[5724]: Invalid user adamma from
83.244.156.204
> > messages:May 11 22:39:51 salle sshd[5724]: Failed
keyboard-interactive/pam for invalid user adamma from 83.244.156.204
port 50954 ssh2
> > messages:May 11 22:41:02 salle sshd[5735]: Invalid user adara from
88.198.47.143
> > messages:May 11 22:41:02 salle sshd[5735]: Failed
keyboard-interactive/pam for invalid user adara from 88.198.47.143 port
33031 ssh2
> > messages:May 11 22:42:28 salle sshd[5738]: Invalid user addison from
62.2.211.46
> > messages:May 11 22:42:28 salle sshd[5738]: Failed
keyboard-interactive/pam for invalid user addison from 62.2.211.46 port
29580 ssh2

> >
> >
> >
> >
>
>
>  --
>  Joel Esler
>    joel.esler@...
>    http://blog.joelesler.net
>  [m]
>
>
>
>
>