practical steps to hack-proofing aws
TRANSCRIPT
Changing your perspective
• How do I secure my business applications in AWS?
• Moving to the cloud =
– Rethinking your perimeter security
• Rethinking how you perform most security tasks:
– Network-based IPs/IDs
– Network scanning
– Penetration tests
– Vulnerability assessments
In the data center
• Setting Up Perimeter Security:
• Setting up your infrastructure
• Setting up access points to the internet
• Configuring firewall, IDS, IPS, etc., at the access points
• Auditing Your Perimeter Security:
• Gather set of IP address blocks to poke at
• Do a port scan (using tools such as Nmap)
• Determine which ports are open on the target
• Try various exploits on the open ports
• Sniff lots of packets
• Dig around to make sure no back doors into the network• Wireless access points, secondary T1 lines, DSL connections
• VPN access from some other network
AWS: What’s different?
• Physical assets secured at
the AWS Availability Zone
• But we still need to guard the AWS API– AWS Identity and Access Management (IAM)
access is your new physical security
The idea of physical security morphs as infrastructure becomes
virtualized by AWS APIs. In a new world of ephemeral, auto-
scaling infrastructure, you need to adapt your security architecture
to meet both compliance and security threats.
Minimizing attack vectors
• Principles don’t change• Reduce your surface area!
• Defense-in-depth
• Some attack vectors don’t change• Application level (user-privilege escalation, web app vulnerabilities, XSS)
• Operating system vulnerabilities
• Database vulnerabilities
• Some attack vectors change• Homogeneous environment
• Polymorphic targets/mapping
• Reduced network sniffing
Perimeter assessments in the cloud
• How do I assess the perimeter of my cloud?
• Old world – Nmap, port scans, ping sweeps, etc.…• Give me your network block
• New world – let me see your configuration• List of publicly accessible resources
• Security groups (Amazon EC2-Classic, EC2-VPC, Amazon Redshift, Amazon RDS, etc.…)
• Routing tables, network ACL
• Amazon VPC, subnets
• Amazon S3 buckets and permissions
• IAM policies
Rules for running pen tests on AWS
http://aws.amazon.com/security/penetration-testing/
• “Complete and submit the AWS Vulnerability/Penetration Testing Request Form to request authorization for penetration testing or scanning of your resources”
• CaveatsAt this time, our policy does not permit testing m1.small or t1.micro instance types. This is to prevent potential adverse performance impacts on the resources you may be sharing with other customers in a multi-tenant environment.
• Demohttps://portal.aws.amazon.com/gp/aws/html-forms-controller/contactus/AWSSecurityPenTestRequest
• Need to know– IP addresses to be scanned (destination)
– Instances IDs
– Scanning IP addresses (source)
What else do we need to cover?
• Amazon EC2 is not our only attack surface
• AWS is a robust, complex platform with many moving parts
• Over 30 different services• Many have unique access control systems
• Some companies have hundreds of AWS accounts
• We need a complete inventory• All publicly accessible endpoints and resources
Hackers find the single weak link
Amazon EC2-Classic
• EC2-Classic is only available in old accounts
• Prevalent for early adopters, pre-VPC era
• Each EC2 instance has • A public IP address and a public DNS name
• A private IP address and a private DNS name
• Can have an Elastic IP Address
• Only security is EC2-Classic security groups
• Treat each as a target with its own security risk
Amazon EC2-VPC
• Default VPC is created in every region
• VPCs are wide open by default
• VPC is composed of:
• Internet and VPN gateways
• Connect to the rest of the world
• 1+ subnet(s)
• Routing tables – how to move traffic around the VPC
• Network ACLs – a firewall but stateless
• Security groups – host-based firewall, stateful
• Resources – EC2, RDS, Amazon Redshift, Amazon ElastiCache
Amazon Simple Storage Service (Amazon S3)
• Up to 100 buckets in an account
• Unlimited number of objects (billions is not uncommon)
• Location
• Within a region, across multi-AZs, not housed in a VPC
• Can’t sit between client and storage
• Security
• Access control through IAM policies, bucket policies, ACLs, and query string authentication
• Server-side encryption, HTTPS support
• Server-access logs (does not integrate with AWS CloudTrail)
• Don’t grant FULL_CONTROL, WRITE_ACP, WRITE permissions to everyone EVER!!!
• Inventory your sensitive data
Amazon Relational Database Service (Amazon RDS)
• Location
• Within a VPC or not, multi-AZ or not
• Security Options
• DB Security Groups (if not in a VPC) or EC2-VPC Security Groups
• Select a non-default database port
• Publicly accessible option
• Not a good idea, but if you do this
• Make sure you use security groups to restrict source IP address
• Make sure you have latest patches applied
• Secure your database snapshots
• Keys to the kingdom if someone can get a copy
• Brute-force passwords, restore to their own account
Amazon Simple Queue Service (Amazon SQS)
• Where does SQS live?
• Within a region, not within a VPC
• Uses a URL such as
• https://sqs.us-east-1.amazonaws.com/123456789012/MySQS
• Security based on policy documents:{
"Version": "2008-10-17",
"Id": "arn:aws:sqs:us-east-1:123456789012:MySQS/SQSDefaultPolicy",
"Statement": [
{
"Sid": "Sid1415217272568",
"Effect": "Allow", "Principal": { "AWS": "*" },
"Action": [
"SQS:ReceiveMessage", "SQS:SendMessage"
],
"Resource": "arn:aws:sqs:us-east-1:123456789012:MySQS"
},
Amazon Simple Notification Service (Amazon SNS)
• SNS does not live inside your VPC
• Permissions based on topic policies:
Using AWS CloudTrail
• An AWS service that records each time the AWS API is called
• Currently supports 20+ AWS services • http://docs.aws.amazon.com/awscloudtrail/latest/userguide/dochistory.html
• Conveniently everything in AWS goes through the API
• Even actions in the AWS Management Console go through the API
• CloudTrail writes files into an S3 bucket
• Near–real time (every five minutes)
• Files are in JSON format
Get started at http://aws.amazon.com/cloudtrail/
Internal vs. external threats
• Understanding who the threat is
• Internal threats• Disgruntled or malicious DevOps
• E.g. Edward Snowden
• External threats• Hacker groups, script kiddies
• E.g. Anonymous
Each requires different controls and monitoring
Example: Code Spaces
• How not to end up like Code Spaces• This is their website now
• Code Spaces hacked• No disaster recovery
• No “offsite” backups
• “Code Spaces: A Lesson In Cloud Backup”
Source: http://www.networkcomputing.com/cloud-infrastructure/code-spaces-a-lesson-in-cloud-
backup/a/d-id/1279116
Tools for securing AWS
• Generic tools fall short
• Purpose-built, not cloud-washed• Make sure tools don’t fall over in the cloud
• Tools have to understand dynamic, ephemeral IPs
• Need a deep understanding of AWS• What does this mean?
• Context is important
• Actionable intelligence
Questions?
On:
• AWS Security
• CloudCheckr
Sign up today for free evaluation
at http://cloudcheckr.com
Aaron Newman is the founder
of CloudCheckr (www.cloudcheckr.com)
Please contact me with additional questions at:
SAN FRANCISCO