Rule:

--
Sid:
2184

--
Summary:
This event is generated when an attempt is made to exploit a known vulnerability in the xlog function of certain Linux NFS Utils packages.

Specifically this event is generated when TCP is used as the attack medium.

--
Impact:
Denial of Service (DoS), possible arbitrary code execution.

--
Detailed Information:
The mountd Remote Procedure Call (RPC) implements the NFS mount protocol. A vulnerability exists in some versions of the Linux NFS Utilities package prior to 1.0.4 that can lead to the possible execution of arbitrary code or a DoS against the affected server.

A programming error in the xlog function may be exploited by an attacker by sending RPC requests to mountd that do not contain any newline characters. This causes a buffer to overflow thus presenting the attacker with the opportunity to execute code.

--
Affected Systems:
Systems using Linux NFS Utils prior to version 1.0.4.

--
Attack Scenarios:
An attacker may send a specially crafted RPC request or mount command to the NFS server that does not contain any newline characters.

--
Ease of Attack:
Moderate.

--
False Positives:
None known.

--
False Negatives:
None known.

--
Corrective Action:
Limit remote access to RPC services.

Filter RPC ports at the firewall to ensure access is denied to RPC-enabled machines. 

Disable unneeded RPC services.

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

Apply the appropriate vendor supplied patches.

--
Contributors:
Sourcefire Research Team
Brian Caswell <bmc@sourcefire.com>
Nigel Houghton <nigel.houghton@sourcefire.com>

--
Additional References:


--
