Rule: -- Sid: 2048 -- Summary: This event is generated when an attempt is made to exploit a known vulnerability in the rsync daemon (rsyncd). -- Impact: Serious. Possible theft of data. -- Detailed Information: rsync is used to synchronize data between two machines across a network. It achieves this by only sending the differences between the files on each host. Since it does not require both hosts to have the data it is synchronizing, it is possible to retrieve a number of files from one host without the corresponding files being present on the receiving host. This event is generated when an attempt is made to cause a buffer overflow condition to occur in the rsync daemon. -- Affected Systems: All systems using rsync. -- Attack Scenarios: The attacker needs to send specially crafted packet data to a host running rsyncd. -- Ease of Attack: Moderate. -- False Positives: Systems using rsync to coordinate sets of data between hosts not in the same LAN. -- False Negatives: None Known -- Corrective Action: Access to files via rsync should be carefully managed using access control lists. The transfer of files from an internal source to an external one should be carefully managed using the appropriate firewall rules. -- Contributors: Sourcefire Research Team Brian Caswell <bmc@sourcefire.com> Nigel Houghton <nigel.houghton@sourcefire.com> -- Additional References: rsync Home: http://samba.anu.edu.au/rsync/ --