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Sid 1-610

Message

PROTOCOL-SERVICES rsh root

Summary

This event is generated when an attempt to login as the superuser is attempted using rsh.

Impact

Serious. If successful the attacker may have gained superuser access to the host.

CVE-2012-6392:

CVSS base score 10.0

CVSS impact score 10.0

CVSS exploitability score 10.0

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

Detailed information

This rule generates an event when a connection is made using "rsh" with the username "root". Such activity is indicative of attempts to abuse insecure machines with a known default configuration.

Some UNIX systems use the "rsh" daemon which permits remote "root" logins. This may allow an attacker to connect to the machine and establish an interactive session. CVE-2012-6392: Cisco Prime LAN Management Solution (LMS) 4.1 through 4.2.2 on Linux does not properly validate authentication and authorization requests in TCP sessions, which allows remote attackers to execute arbitrary commands via a crafted session, aka Bug ID CSCuc79779.

Affected systems

  • cisco primelanmanagement_solution 4.1
  • cisco primelanmanagement_solution 4.2
  • cisco primelanmanagement_solution 4.2.1
  • cisco primelanmanagement_solution 4.2.2

Ease of attack

Simple, no exploit software required

False positives

A system administrator may be logging in to a host using the username "root"

False negatives

If a local username is not the same as the remote one ("root"), the rule will not generate an event.

Corrective action

Investigate logs on the target host for further details and more signs of suspicious activity

Use ssh for remote access instead of rsh.

Deny remote root logins to the host, use a normal user and "sudo" or give the user the ability to "su" to root where appropriate.

Contributors

Additional References

  • tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130109-lms