SSH Jump Server, SSH Bastion host, SSH Jump host for PCI DSS and other security compliance

ssh jump server

SSH Jump server or Bastion host would be a fortified central server or gateway server where all your staff would login in first via ssh before accessing any other servers behind it. The fortified server is also known as Bastion Host or SSH Jump Host or SSH Jump Box. The jump host assist in securing  PCI DSS and other security compliances.

Using an intermediate ssh jump server increases security and ease of managing your Linux  production servers. Ezeelogin is an ssh gateway software that would help you setup your secure jump server very quickly and comes with lots of security and automation features. The below diagram would give you a better idea of how the ssh jump server works

 

ssh Bastion host ssh Jump server ssh gateway
SSH Gateway – SSH Bastion Host – SSH Jump Host – SSH Jump Box – SSH Jump Server

Advantages in using  ssh Jump Server ( also called a ‘Bastion Host’ )?

  • Built in Identity and Access Management for your staff
  • Intuitive SSH interface to access Linux nodes
  • SSH access to Linux production servers for your staff without sharing the ssh private keys or password
  • Two factor authentication in ssh and for the panel. Yubikey , Google Authenticator, Duo Security 2FA integrated.
  • Record ssh session of your system administrator or devops engineers for performing forensic audits so that you know who does what on which server and when.
  • Privileged Access management so that you know who gets root access and who gets non privileged access.
  • SSH Key management so that you can rotate the keys easily on multiple servers.
  • Root Password management so that you can reset the root password on servers in a click.
  • Parallel Shell integrated so you can execute command on many server simultaneously.
  • Root password management for your Linux server in production
  • Access Control panel like Cpanel/WHM and more in a click
  • PCI DSS 3.2, SOX, SOC2, FFIEC, NERC CIP, ISO 27001 & HIPPA Compliance requirements can be met quickly
ssh jump server
ssh jump server interface

 

 

SSH Key Management

 

ssh key management
ssh key management

SSH key based authentication  is the default method that any Linux admin would choose for  granting ssh access to  Linux servers or Linux cloud instances. SSH key based  authentication is the preferred method since its far more secure and more popular than password based authentication. The two commonly used   keys for authentication are RSA and DSA and RSA Keys are preferred since DSA is known to be vulnerable.

Its good to have SSH Key based authentication but imagine the amount of management that has to be done if you have 100 employees and have 1000 Linux instances and how do you  grant access to the employees to the thousand Linux servers or Linux cloud instances? How do you add the ssh keys to grant access ?  How do you remove the ssh keys when the employee leaves the company? How do you rotate the keys?

You would have to manually add the keys to all the Linux servers and cloud  instances to grant access and when an employee leaves, you would have to ensure that the employees public keys are removed from all your servers failing which it becomes a serious security issue.

Ezeelogin helps you address the following issues

  1. SSH  Key rotation
  2. Centralised ssh key management
  3. Helps to reduce the overhead that comes with managing the ssh keys to almost zero.

 

Parallel Shell

Parallel shell – Run commands on multiple Linux servers or Cloud instances   simultaneously

If you are in charge of large server farms, cluster of Linux nodes for high performance computing, or cryptocurrency mining farms then parallel shell would easily let you manage multiple Linux servers or Cloud instances easily and quickly.

Parallel shell is built into the backend shell of the Ezeelogin SSH Jump host. You can work with it as you would work on a normal bash shell and the command would be simultaneously executed on multiple Linux servers.

Imagine, that you are the security engineer in charge for fleet of linux server or aws instances. One fine morning as you are going through your daily job routine you are notified of a critical kernel vulnerability.  As a responsible security officer, you do not want to postpone patching the kernels for the next day  as the longer the delay to patch the Kernel, greater the possibility of a security breach.

In such critical scenarios, the parallel shell feature could be extremely useful as you can compile kernel  on one thousand machine at the time of compiling a kernel for one server.

This feature is a god send for many , however with great powers come great responsibilities.  The image shows a command being executed in using parallel shell.

parallel shell
parallel shell- Multiple Linux server management

Some of the benefits of this feature are

  1. Improve productivity of your system administrators and devops engineers
  2. Improve the efficiency with which Linux nodes or cloud or aws instances are managed.
  3. Easily execute command simultaneously on group of servers. There are no hard configurations to be done.
  4. Better and faster management of Linux server and cloud instances.
  5. Easily copy files across group of servers
  6. Server orchestration would be very easy if you have many Linux instances.
  7. There is no need to install agents on remote machines
  8. Faster setup
  9. Delivery faster services
  10. Runs on OpenSSH

SSH Two Factor Authentication

ssh jumpbox with duo two factor authentication
SSH gateway and Jumphost with DUO 2FA o

 

SSH JumpHost and SSH Gateway Ezeelogin supports DUO Security two factor authentication ( 2FA ) which means that anyone having a smartphone these days can easily use it for the second layer of authentication. With DUO, you dont have to type in complex strings or numbers, just tap on the smartphone screen and you are securely authenticated easily. No extra devices like RSA Keys or security token generating devices has to be carried since you already have a smartphone with you to authenticate into your SSH Gateway.

OpenSSH 7.0 disables DSA keys by default


The road ahead was never bright for DSA keys and the writing was clear
on the wall. Ezeelogin SSH gateway will be dropping DSA keys and would 
be using ONLY RSA keys in future releases. 
Starting with the 7.0 release of OpenSSH, support for ssh-dss keys has
been disabled by  default at runtime due to their inherit weakness.If
you rely on these key types,you will have to take corrective action or 
risk being locked out. Your best option is to generate new keys 
using strong algos such as rsa or ecdsa or ed25519.RSA keys will give
you the greatest portability with other clients/servers while ed25519
will get you the best security with OpenSSH.(but requires recent versions of
client & server).

If you are stuck with DSA keys, you can re-enable support locally by updating
 your sshd_config and ~/.ssh/config files with lines like so: 
     PubkeyAcceptedKeyTypes=+ssh-dss

Be aware though that eventually OpenSSH will drop support for DSA keys entirely, 
so this is only a stop gap solution.

More details can be found on 
OpenSSH's website: http://www.openssh.com/legacy.html

Automated root password management on Linux servers

Automatic root password management
Automatic root password management

 

Boss wants you to enable password based authentication on hundred  Linux server, he wants you to  set 30 plus character strong password on each server, share the root passwords with  developers ,  change the root passwords again once the developers logs out of the servers at the end of the day, also your boss want you to reset the root password on all the Linux server on a daily basis  as he is paranoid  when it comes to security.

Well without eating your boss alive and instead to get a promotion, here is the magic wand, use the Ezeelogin root password management feature and you will  be able to meet all his requirement and if not even better. Being a Linux system administrator you know for fact that Key based authentication are exponentially stronger even if your passwords are 100 characters long but for some unearthly reasons you need to have password based authentication enabled on your hundred Linux servers.

 

jump server password view
jump server password view

Here are the key issues that Ezeelogin root password management features addresses.

  • Automatically set and reset and strong root passwords up to 32 characters long in a click on hundreds or thousands of Linux servers
  • Schedule periodic reset of root password across all your linux servers in a click
  • Reset root passwords on all your Linux server in a click.

 

 

 

 

Record SSH Session

record ssh sessions
Record SSH Session

Record ssh sessions on Linux server, Amazon EC2  instances for Security Compliance

It is mandatory to record ssh sessions to be PCI DSS Complaint when system administrator, system engineers or devops engineers login via ssh into your Linux machines or cloud instances, . It is also a must to maintain a log of all ssh activities on your Linux servers. This is tedious task for any Linux system administrator as deploying a improvised solution has often turned to be useless in the hour of need.

Why you should record ssh session of your staff /employees on a bastion host ?

Imagine that you have 100 Linux servers or cloud instances. You have 100  users  having access to these server via SSH with some system admins having privileged access or root access. If a user deletes a critical files or a database record which leads to a serious downtime and million of dollar lost in revenue,  following are some of the questions that you would have to answer as the security officer of your Linux infrastructure

  • Which user did it ? How will you find out who is responsible when you have so many of your employees accessing your servers?
  • How did it happen? When did it happen?
  • What is the extent of damage?
  • How will you prevent this in the future?
  • Is it possible to track  ssh server activities of employees?
  • Is it possible to do a forensic investigation when somebody does something bad like opening a backdoor?
  • How to monitor a staff in ssh in real time?
  • Has any Linux  server been breached?
  • How  to ensure that your employees password typed in on STDIN are not recorded as required by security compliances ?
    Enabling the SSH Session recording feature in the Ezeelogin SSH jump server would help you achieve this very quickly and easily so you have a complete record of what was done on your server at any point of time by which jump server user. This is very useful for forensic audits or for maintaining an audit trail for pci compliance.
    The solution records every ssh activity.  It includes the user input and the output with timestamps.  There is provision to search through the recorded ssh logs as well.

Bastion host – How to secure and harden the ssh server on it?

  1. Enable a firewall and by default block all  IP access to the SSH Port and enable only your staff ips or dynamic ip ranges that you trust.
  2. Disable direct root login. Its always better to login as a non privileged user first and the switch to the root user. This is the norm if you are looking for PCI DSS Compliance.Edit /etc/sshd/sshd_config
    PermitRootLogin noEzeelogin SSH Gateway has a feature called ‘AUTO SU or SUDO’ which would automatically does the switching part  so you would not waste your time retrieving password of the ‘admin’ user and then entering the root password.
  3. Disable password based authentication and enable only Key based authentication in the  sshd configuration file. I would rate this as the most important of all.

    PasswordAuthentication no

  4. Enable Key based authentication. RSA is know to be more secure than DSA keys.

    RSAAuthentication yes

    PubkeyAuthentication yes

     

  5. Change the sshd default listening port from 22 to something like 22656 since its hard to guess and attackers would have to scan.Use custom SSH Port and Listening IPs.
    Port 22656
    ListenAddress 192.168.5.6.123
  6. Configure a VPN and having your server behind a VPN is good idea. This would really improve the security and harden the server.