Event Query

During monitoring, you see numerous telnet attempts from source IP 189.168.10.22. Telnet attempts could be an attack. Telnet potentially allows an attacker to remotely connect to a remote computer as if they were locally connected. This can lead to unauthorized configuration changes, installation of programs, viruses, and so on.

You can Event Query to determine how often this possible attacker has attempted a telnet; you can setup a filter to query for this particular attacker. For example, you know the following:

  • Source IP: 189.168.10.22

  • Destination IP: 189.168.10.23

  • Severity: 5

  • Event Name: Attempted_telnet

  • Sensor Type: H (Host Intrusion Detection)

To Perform an Event Query:

  1. In the Sentinel Control Center, click Event Query (magnifying glass icon) and click the Filter drop-down menu.

  2. A window with a list of filters displays. Click Add; enter a filter name of telnet SIP 189_168_10_22. In the field below the Filter, enter:

    • SourceIP = 189.168.10.22

    • EventName = Attempted_telnet

    • Severity = 5

    • SensorType = H

    • DestinationIP = 189.168.10.23

    • Match if, select All conditions are met (and)

    1. Click Save. Highlight your filter and click Select.

    2. Enter your time period of interest; click Search (magnifying glass icon). The results of your query appears. If your Event Query makes a match, you will get a result similar to the following illustration.

    image\ebx_-34268994.gif

    If you want to see how often in general this user is attempting a telnet, remove DestinationIP, SensorType and Severity from your filter or create a new filter. The results will show all the destinationIPs this user is attempting to telnet to.

    If any of your events are correlated events, you can right-click > View Trigger Events to find what events triggered that correlated event.

    NOTE: Correlated events will have the SensorType column populated with a C.

    Another event of interest could be excessive FTP events. This can also be a remote connection, allowing for transferring, copying and deleting of files.

    Below is a short list of attacks of interest. Types of attacks are an extensive list. For more information about network/host attacks, there are many resources available (that is, books and the internet) that explain different types of attacks in detail.

    • SYN Flood 

    • ICMP and UDP Flood

    • Packet Sniffing

    • Denial of Service  

    • Smurf and Fraggle

    • Dictionary Attack