Hi Daniel,

first of all we tried the server-location "local" and attack the agent
again, the connection between the server and the attacker was 
disconnected but the connection between the attacker and the 
agent-server still works fine!

We understand the location local, but it doesn't work at our side. And 
we reinstalled the agent and the server. But it doesn't fixed our problem.

The server recognized that attack from the IP 192.168.7.56 in the file 
/var/ossec/logs/active-response.log:
Tue Jun 10 08:11:26 CEST 2008 
/var/ossec/active-response/bin/firewall-drop.sh add - 192.168.7.56 
1213078286.11069 31101
But on the agent-side the same file doesn't exists!

The Web-Interface also show us the possible attack (after the timeout is 
expired):

2008 Jun 10 08:10:31 Rule Id: 5710 level: 5
Location: (agent) 192.168.7.219->/var/log/auth.log
Src IP: 192.168.7.56
Attempt to login using a non-existent user
Jun 10 08:10:31 agent sshd[2255]: Failed password for invalid user test 
from 192.168.7.56 port 1208 ssh2



We changed the location-entry back to: defined-agent and restart the 
server again. The secure connection between server and agent seems to 
work! The logfiles on the server and the agent have no errors that shows 
problems in the communication.

Server-Side: OSSEC HIDS agent_control: Restarting Syscheck/Rootcheck on 
agent: 002
The syscheck on the agent starts one or two minutes later.

Hm, where is the problem?
Exists there still a problem between SLES and Debian?

Thanks for your help.



> Hi Joachim,
> 
> Your configuration seems fine, so it should be working. Can you show
> us the alert that
> you expected the active response to run (from
> /var/ossec/logs/alerts.log )? Also, can
> you show the file /var/ossec/logs/active-response.log from the agent?
> 
> *Note that the timeout is set to 300 seconds, so after 5 minutes, the
> entry will be removed from the agent's firewall.
> 
> **You said that when you changed to "local" and attacked the agent,
> that the server blocked your
> access. Are you sure about that? When you set to "local", ossec will
> block in the agent that
> reported the alert.
> 
> Thanks,
> 
> --
> Daniel B. Cid
> dcid ( at ) ossec.net
> 
> On Mon, Jun 9, 2008 at 3:14 AM, Joachim Krais
> <[EMAIL PROTECTED]> wrote:
>>
>> Hello together,
>>
>> we use OSSEC as server/agent on SLES9 (OSSEC-server) and Debian Servers
>> (OSSEC-agent). We want to react on unautherized access/connections at
>> the agent side. The secure connection between the agent and the server
>> is established. The agent sends data to the server. The server and the
>> agent are correct installed as server and agent.
>>
>> We have the problem, that the agent or the server doesn't react by
>> active response.
>> In the OSSEC-logfile on the agent-side we can't find any recognition.
>> If we change the location in the server-configuration to local and we
>> attack the agent, the server locks our connections for the configured
>> time but the agent doesn't react!
>>
>> We use OSSEC Version 1.5.
>> Where is the problem?
>> Here is the server-configuration:
>>
>>   <command>
>>     <name>firewall-drop</name>
>>     <executable>firewall-drop.sh</executable>
>>     <expect>srcip</expect>
>>     <timeout_allowed>yes</timeout_allowed>
>>   </command>
>>
>>
>>   <!-- We act on this IDs:
>>     11251-53: proftp
>>     11451,52: vsftp
>>     5701,5703,5705,5710,5712,5719,5720: ssh
>>     30114: apache
>>     31151-54,31161: webrules
>>     5631: telnet
>>     5551: pam
>>     40601: attack
>>   -->
>>
>>
>>   <active-response>
>>     <command>firewall-drop</command>
>>     <location>defined-agent</location>
>>     <agent_id>002</agent_id>
>>     <rules_id>5701,5703,5705,5710,5712,5719,5720,40601</rules_id>
>>     <timeout>300</timeout>
>>   </active-response>
>>
>>
>> Could anybody help us?
>> Thanks a lot.
>>
>> Joachim Krais
>>


-- 
Mit freundlichen Grüßen
Joachim Krais

Deutsche Telekom AG
Zentrum Technik Netzmanagement
Joachim Krais, Dipl.Ing.(FH)
Systemingenieur NIP1 Central Servers
Olgastr. 67, 89073 Ulm
+49 731 100-84416 (Tel.)
+49 731 100-84066 (Fax)
+49 171 3027783 (Mobil)
E-Mail: [EMAIL PROTECTED]
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