Rule:--Sid:2012--Summary:CVS is the Concurrent Versions System, commonly used to help manage software development.--Impact:This may be an intelligence gathering activity or an attempt to connect to CVS using the credentials of a user with escalated privileges. Shouldthis attempt be succesful the entire CVS repository may be compromised.--Detailed Information:This rule detects attempts to connect to a CVS repository that fail due determined activity by an attacker to gain unauthorized access to the CVS respository.The source code of software in the repository may be compromised by a succesful attacker who could choose to insert malicious code of his own making.For CVS daemons running under changed root conditions (chroot), the restof the operating system files may be protected but the entire CVS directory structure and contents is vulnerable.--Affected Systems:	All versions of CVS	--Attack Scenarios:This may be an intelligence gathering activity or an attempt to log in to CVS using the credentials of an authorized user.--Ease of Attack:Simple.--False Positives:It is possible that the cvsroot on the server is misconfigured. Check permissions on the cvsroot to ensure the repository is writable by the cvsdaemon.--False Negatives:Connections to the server using zlib compression will not generate thisevent.--Corrective Action:Disable the CVS daemon in the file /etc/inetd.conf. Run the CVS daemon as a user other than root that does not have a valid login to the machine.Disable anonymous cvs access to the server where appropriate.Maintain checks on the password database and the CVS repository.--Contributors:Sourcefire Research TeamBrian Caswell <bmc@sourcefire.com>Nigel Houghton <nigel.houghton@sourcefire.com>--Additional References:CVS:http://www.cvshome.org/docs/--