Software Engineering Institute

VERITAS Backup Exec is a data backup and recovery solution with support for over the network backup. The VERITAS Backup Exec Agent runs on systems to be backed up listening on TCP port 10000 and is responsible for accepting connections from the backup server when a backup is to occur.

The Backup Exec Remote Agent for Windows Servers contains a buffer overflow vulnerability due to incorrect validation on authentication requests, allowing a remote attacker to execute arbitrary code.

For more details on the vulnerability, see the iDefense security advisory:

http://www.idefense.com/application/poi/display?id=272&type=vulnerabilities.

For information about affected software versions and patching please the VERITAS Software Security Advisory.

VERITAS Software has released information about this and five other security issues affecting VERITAS Backup Exec for Windows and Netware Servers. For more information about this specific vulnerability please see:

VERITAS Software Security Advisory VX05-002 available from http://seer.support.veritas.com/docs/276604.htm.

Information on the other vulnerabilities along with patch details can be found at:

http://seer.support.veritas.com/docs/277428.htm.

NOTE: We are aware of publicly available exploit code circulating in the wild and have received credible reports of compromise. Additionally, we can confirm significant increases in the levels of network activity directed at TCP port 10000 from the evening of June 25, 2005.

A remote attacker can execute arbitrary code on computers where the Remote Agent is installed and gain administrative control. As the Backup Exec Remote Agent may be running on workstations as well as servers, this vulnerability may provide greater opportunity for attack than the other vulnerabilities identified above.

Apply a patch from the vendor. See http://seer.support.veritas.com/docs/276604.htm for details.

Workaround

Use firewalls to limit connectivity so that only the backup server(s) can connect to the systems being backed up. The standard port for this service is port 10000.

At minimum, some basic protection should be in effect at the network boundaries. Individual installations may operate on nonstandard ports, which should be taken into account when developing network traffic filtering rules.

Note: even if patching can be done quickly, the above workaround measures should be considered as part of a defense-in-depth strategy for protecting your systems.