2451.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:
2451

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Summary:
This event is generated when a user in your network has successfully registered with a Yahoo Instant Messenger server to receive voice chat messages or is receiving voice chat messages.

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Impact:
Possible policy violation.  Instant Messenger programs may not be appropriate in certain network environments.

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Detailed Information:
Yahoo IM voice chat allows IM users to exchange audio messages.  This activity may not be appropriate in a corporate environment.

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Affected Systems:
Any host running Yahoo Instant Messenger.

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Attack Scenarios:
This particular type of Yahoo IM exchange has no known attacks, however it may represent a policy violation because the host is running Yahoo IM.

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Ease of Attack:
Easy to exchange voice messages.

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False Positives:
None Known.

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False Negatives:
It may be possible for Yahoo IM traffic to use other ports than the default expected ones.  

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Corrective Action:
Disallow the use of IM clients on the protected network and enforce or implement an organization wide policy on the use of IM clients.

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Contributors:
Sourcefire Research Team
Judy Novak <[e-mail]>
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Additional References:
Yahoo Protocol
http://www.cse.iitb.ac.in/~varunk/YahooProtocol.htm

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