cyberstrikeus CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0 - Control 4.2.17
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Description
The MaxStartups parameter specifies the maximum number of concurrent unauthenticated connections to the SSH daemon.
Rationale
To protect a system from denial of service due to a large number of pending authentication connection attempts, use the rate limiting function of MaxStartups to protect availability of sshd logins and prevent overwhelming the daemon.
Audit Procedure
Command Line
Run the following command and verify the output:
sshd -T | grep -i maxstartups
Expected Result
maxstartups 10:30:60
OR more restrictive.
Remediation
Command Line
Edit the /etc/ssh/sshd_config file to set the parameter as follows:
MaxStartups 10:30:60
Default Value
MaxStartups 10:30:100
References
- NIST SP 800-53 Rev. 5: CM-6
CIS Controls
None
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Assessment Status
Automated