Rule:

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Sid: 
4638

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Summary: 
This event is generated when an attempt is made to exploit a known vulnerability in Tcpdump. In particular, this event indicates that the exploit was attempted via a malformed Resource Reservation Protocol (RSVP) packet.

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Impact: 
Serious. Denial of Service (DoS). Code execution may be possible.

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Detailed Information:
Tcpdump is a packet capture utility used on various BSD, Linux and UNIX style operating systems.

An error in the processing of the payload length in an RSVP packet may prevent an attacker with the opportunity to overflow a fixed length buffer and execute code of their choosing in the context of the user running tcpdump. This is normally the super-user or administrator when tcpdump is used to sniff data directly from a network interface.

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Affected Systems:
	Tcpdump 3.9.1 and prior
	Tcpdump 3.8.3 and prior

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Attack Scenarios: 
An attacker need to craft an RSVP packet with a packet payload length of 0 to cause the overflow to manifest itself.

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Ease of Attack: 
Simple.

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False Positives:
None Known

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False Negatives:
None Known

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Corrective Action: 
Apply the appropriate vendor supplied patch

Upgrade to the latest non-affected version of the software.

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Contributors: 
Sourcefire Research Team
Alex Kirk <akirk@sourcefire.com>
Nigel Houghton <nigel.houghton@sourcefire.com>

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Additional References:

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