AWS Security Groups

How to Manage a Security Group on AWS Cloud

The Amazon EC2 service allows you to add and remove instances dynamically for the purpose of scalability. However, the above mentioned scalability need and auto addition of the instances can cause issues for firewall configuration and maintenance, which traditionally rely on IP addresses, subnet ranges or DNS host names as the basis for the firewall rules.

The Amazon EC2 provides a firewall to assign to the EC2 instances. The AWS EC2 firewall is configured through the user-defined groups.  When new instances are launched or additional instances are added or removed, the appropriate rules are enforced. Similarly, if the user changes a rule for a group, the changes are automatically applied to all the members of the group.

The present guide demonstrates how to manage a security group.

EC2 How-to: View or Update an AMI Permissions

The 5 Biggest Security Mistakes Users Make in Amazon’s Cloud

The following article was posted on GigaOm and was based on our analysis and cloud security insights that Newvem’s big data engine reveals. In this article, you will find 5 important low hanging fruits that you should recognize in order to have your Amazon cloud account secure. If you are an Amazon cloud services’ user, we invite you to connect your AWS cloud account to our non-intrusive service in order to know your cloud and learn more, not only your AWS security, but also about money that you’re wasting, point of failures (POFs) and poor performance yields.

Amazon AWS IAM – Several Tips and Practices

The cloud presents many security management challenges. Ensuring compliance, identity management, and other security best practices can be a challenging task. AWS Identity and Access Management (IAM) is one of the tools that can be used to mitigate the risks associated with these challenges. In this article, I will discuss a few of the high points of IAM, including the different options and limitations that this AWS service brings together with its fascinating capabilities.

Many cloud computing users strive to apply security best practices to their cloud computing strategies. One of the best components that Amazon offers to manage security in their cloud computing service is their IAM mechanism, which allows an account owner to create users and manage their permissions within an AWS account.

AWS EC2 Security Groups Usage – How secure is your data in the cloud?

Mistake #9: Failing to Proper Configure AWS Security Groups

Amazon’s approach to security is based on “shared responsibility” between users and AWS – Security Groups is one of the tools Amazon provides for users to fulfill their part. One would expect that when it comes to security, users don’t err.

Unnecessary Security Groups Ports are Open on DB Server

We have noticed that at least one unnecessary port is open on your DB server, meaning that your DB server is potentially vulnerable. Typically this issue occurs when using the same security groups to secure DB and non-DB servers. We suggest setting security groups specifically for the DB server and limiting access to recommended DB-related ports only.

IP Ports are Open to all Internal AWS Servers

We have found that you have at least one of your security groups’ IP ports open to all internal AWS servers. This can potentially make some of your servers vulnerable. This issue can occur if one of your security groups was configured to allow access to the following IP range -  

Open IP ports

Newvem monitors your security groups’ ports, and notifies you if it finds that at least one of them is currently open to all IP addresses. An open IP port may mean that some servers are exposed to access from any IP address worldwide, making them vulnerable. We suggest that you reduce the number of open ports to a minimum, limiting access from the outside world only to web-facing services. For example, port 80 for HTTP and port 443 for HTTPS.

Newvem Insight: Critical IP Ports are Open: Identification, View and Set Security Groups Rules


Our identification of the issue is based on the following data:

  • One or more security groups were configured to allow access through critical IP ports.
  • One or more of your AWS instances are using the security group with the open critical IP ports.
Newvem Group Security Assessment 

The following is a list of critical IP ports:

Port # Subject
5432 Postgres
3306 MySql
3362 MySql
1433 Sql Server
389 LDAP
9160 Cassandra
27170 MongoDB
5672 AMQP
11211 Memcached
Viewing a Security Group’s Rules
  •  AWS Management Console
    1. Log in to the AWS Management Console and click the Amazon EC2 tab.
    2. In the Navigation pane, click Security Groups. The security groups belonging to the account are displayed.
    3. Select the security group whose rules you want to see. The security group’s information is displayed in the lower pane in the Details tab; its rules are displayed in the Inbound tab.
  • Using AWS CLI Command Line Tools - 

 Type the command:

PROMPT>  ec2-describe-group [group ...]

Amazon EC2 returns output in the format of the following example.

GROUP   sg-251s6f45     999988887777    WebServers   web

PERMISSION      999988887777    WebServers ALLOWS  tcp     80      80      FROM    CIDR       ingress

Tip: To filter the list to return only the security group with the open ports, use the ip-permission.from-port and filters.

Note: These are a short explanations based on our detailed how-to guide - How to Add a Rule to an AWS Security Group

Adding a Rule to a Security Group

AWS Management Console

To add a rule to a security group -

  1.  In the AWS Management Console, select a specific EC2 security group, by following the instructions in the above procedure (Viewing a security group’s rules). The selected security group’s rules appear in the lower pane, in the Inbound tab.
  2. In the Inbound tab, in Create a new rule, select the type of rule to create.
  3. In Port range, specify a port or port range. In this case of open critical IP ports, we suggest that you reduce the number of open ports to a minimum, limiting access from the outside world only to web-facing services (e.g. port 80 for HTTP and port 443 for HTTPS).
  4. In Source, specify one of the following:
    • The name or ID of the security group that is allowed access. If the group is in someone else’s AWS account, type the AWS account ID that contains the security group, followed by “/”, followed by the security group name. For example:  978644442091/SecurityGroupA.
    • The IP address or range of addresses in CIDR notation that is allowed access. For example, 123.2.432.3 to limit access to one computer at that IP address; 123.2.432.3/24 to limit access to a network at that range of IP addresses. You can enter to allow all IP addresses to access the specified port range.

5. Click Add Rule. An asterisk appears on the Inbound tab, and the Apply Rule Changes button becomes enabled.

6. Click Apply Rule Changes. The new rule is created and can be viewed in the right pane of the Inbound tab. The new rule is applied to all instances belonging to the selected security group.

Note: These are a short explanations based on our detailed how-to guide - How to Add a Rule to an AWS Security Group

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Keywords: critical IP ports, amazon aws security groups, AWS management console, security group rule, amazon ec2, aws instances,

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