Mail relay is a feature that allows SMTP servers to act as open gateways through which mail applications can send e-mail. Commercial operators, who send millions of unwanted spam e-mails, often target mail relay for exploitation. Most organizations now restrict mail relay services to specific domain users.
To configure spam relay settings:
This e-mail address should be external to your organization, such as a Yahoo! or Hotmail address. The application will attempt to send e-mail from this account to itself using any mail services and mail scripts that it discovers during the scan. If the application receives the e-mail, this indicates that the servers are vulnerable.
This is typically a Web form that spammers might use to generate Spam e-mails.
Nexposeperforms several classes of vulnerability and policy checks against a number of databases, including:
For all databases, the application discovers tables and checks system access, default credentials, and default scripts. Additionally, it tests table access, stored procedure access, and decompilation.
To configure to scan database servers:
Nexpose attempts to verify an SID on a target asset through various methods, such as discovering common configuration errors and default guesses. You can now specify additional SIDs for verification.
You can configure Nexpose to scan mail servers.
To configure to scan mail servers:
This setting is the interval at which the application retries accessing the mail server. The default value is 30 seconds.
This setting is a threshold outside of which the application will report inaccurate time readings by system clocks. The inaccuracy will be reported in the system log.
Nexpose tests a number of vulnerabilities in the Concurrent Versions System (CVS) code repository. For example, in versions prior to v1.11.11 of the official CVS server, it is possible for an attacker with write access to the CVSROOT/passwd file to execute arbitrary code as the cvsd process owner, which usually is root.
To configure scanning CVS servers:
DHCP Servers provide Border Gateway Protocol (BGP) information, domain naming help, and Address Resolution Protocol (ARP) table information, which may be used to reach hosts that are otherwise unknown. Hackers exploit vulnerabilities in these servers for address information.
To configure Nexpose to scan DHCP servers:
Telnet is an unstructured protocol, with many varying implementations. This renders Telnet servers prone to yielding inaccurate scan results. You can improve scan accuracy by providing Nexpose with regular expressions.
To configure scanning of Telnet servers:
For more information, go to Using regular expressions.