238.txt

snort入侵检测规则文件2.4 Snort是众所周知的网络入侵检测工具

Rule:
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Sid:
238

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Summary:
This event is generated when a Tribe Flood Network (TFN) Distributed Denial of Service (DDoS) daemon responds to a client request to spawn a shell.

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Impact:
Attempted DDoS.  If the listed source IP is in your network, it may be a TFN daemon.  If the listed destination IP is in your network, it may be a TFN client.

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Detailed Information:
The TFN DDoS uses a tiered structure of compromised hosts to coordinate and participate in a distributed denial of service attack. Clients communicate with daemons to inform them to launch attacks. A daemon will respond with a client request to spawn a shell with an ICMP echo reply with an ICMP identification number of 123, an ICMP sequence number of 0 and a string of "shell bound to port" in the payload.   

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Affected Systems:
Any TFN compromised host.

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Attack Scenarios:
After a host becomes a TFN daemon, it will respond to client requests.

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Ease of Attack:
Simple. TFN code is freely available.

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False Positives:
None Known.

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False Negatives:
None Known.

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Corrective Action:
Perform proper forensic analysis on the suspected compromised host to discover the means of compromise.

Rebuild a confirmed compromised host.

Use a packet-filtering firewall to block inappropriate traffic to the network to prevent hosts from being compromised.

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Contributors:
Original rule written by Max Vision <[e-mail]>
Sourcefire Research Team
Judy Novak <[e-mail]>

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Additional References:

CVE:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2000-0138

Arachnids:
http://www.whitehats.com/info/IDS182

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