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Introduction:
The migration to cloud infrastructure has introduced a new frontier of security challenges, where misconfigurations and excessive permissions often serve as the primary attack vector. A recent hands-on cloud security incident response exercise, utilizing the Wiz platform, demonstrates how attackers leverage exposed assets and identity risks to compromise AWS environments. This article deconstructs the tactics, techniques, and procedures (TTPs) observed in such incidents, providing a practical guide for security professionals to investigate, mitigate, and prevent similar breaches.
Learning Objectives:
- Understand the common misconfigurations in AWS that lead to initial compromise and lateral movement.
- Learn the essential command-line and API-based techniques for investigating cloud security incidents.
- Develop a proactive hardening strategy using CSPM principles and automated tooling.
You Should Know:
1. Identifying Publicly Exposed Critical Assets
The first step in a cloud attack chain is often the discovery of publicly accessible, sensitive resources like S3 buckets or EC2 instances with weak security groups.
Verified Commands & Tutorials:
– `aws s3 ls s3://bucket-name/ –no-sign-request` – Lists the contents of an S3 bucket without authentication if it is publicly readable.
– `nmap -sV -p 22,80,443,3389
– `aws ec2 describe-security-groups –group-ids
Step-by-Step Guide:
An attacker begins reconnaissance by scanning IP ranges for open ports or using tools to discover S3 buckets. The `aws s3 ls` command with the `–no-sign-request` flag is a direct way to test for public read access on a bucket. If successful, it lists the objects, potentially exposing sensitive data. Similarly, `nmap` identifies if management ports like SSH (22) or RDP (3389) are exposed to the entire internet (0.0.0.0/0), a critical misconfiguration. The `describe-security-groups` command is used from an authenticated perspective to audit which IP ranges are allowed through the firewall.
2. Exploiting Over-Privileged IAM Identities
Once inside the environment, attackers pivot by searching for compute resources (like EC2 instances) with attached IAM roles that have excessive permissions.
Verified Commands & Tutorials:
– `curl http://169.254.169.254/latest/meta-data/iam/security-credentials/` – Retrieves the name of the IAM role attached to the EC2 instance from the Instance Metadata Service (IMDS).
– `curl http://169.254.169.254/latest/meta-data/iam/security-credentials/
– `aws sts get-caller-identity` – Using the stolen credentials, the attacker confirms their new identity.
Step-by-Step Guide:
If an attacker gains command execution on an EC2 instance (e.g., via a vulnerable web application), they can query the IMDS. The first command fetches the role name. The second command returns temporary access keys, a secret key, and a session token. These credentials are then configured in a new AWS CLI profile on the attacker’s machine. Running `aws sts get-caller-identity` validates the assumed role and reveals the ARN, showing the level of access achieved.
3. Enumerating Permissions for Lateral Movement
After obtaining credentials, the attacker must discover what those credentials are authorized to do.
Verified Commands & Tutorials:
– `aws iam list-attached-user-policies –user-name
– `aws iam list-attached-role-policies –role-name
– `aws iam get-policy-version –policy-arn
– `aws iam simulate-principal-policy –policy-source-arn
Step-by-Step Guide:
Using the assumed role’s credentials, the attacker runs `list-attached-role-policies` to see which AWS managed policies are attached. For each policy ARN returned, they use `get-policy-version` to fetch the JSON policy document. This reveals permissions like `s3:` (full S3 access) or `iam:PassRole` (a powerful privilege escalation vector). The `simulate-principal-policy` command provides a more targeted way to test for high-risk actions without generating logs in CloudTrail.
4. Privilege Escalation via PassRole and EC2
A common escalation path involves abusing the `iam:PassRole` and `ec2:RunInstances` permissions together.
Verified Commands & Tutorials:
– `aws iam list-roles` – Lists all IAM roles in the account to find a high-privileged role to target.
– `aws ec2 run-instances –image-id ami-xxxxxx –instance-type t2.micro –iam-instance-profile Name=
– `aws ec2 associate-iam-instance-profile –instance-id
Step-by-Step Guide:
If the compromised role has `iam:PassRole` (for a specific role) and ec2:RunInstances, the attacker can create a new EC2 instance and pass a more powerful role to it. They first use `list-roles` to identify a target role, such as AdministratorAccess. Then, they execute run-instances, specifying the target role in the `–iam-instance-profile` parameter. Once the instance is running, they can access its IMDS to steal the new, more powerful credentials, effectively escalating their privileges to admin level.
5. Data Exfiltration from Compromised Environments
With elevated access, exfiltrating data is a primary goal, often achieved through S3 or database snapshots.
Verified Commands & Tutorials:
– `aws s3 sync s3://sensitive-bucket ./local-dump/` – Synchronizes the entire contents of an S3 bucket to a local directory.
– `aws rds create-db-snapshot –db-instance-identifier
– `aws rds modify-db-snapshot-attribute –db-snapshot-identifier
Step-by-Step Guide:
The attacker uses `aws s3 sync` to download the entire contents of a bucket identified during reconnaissance. For databases, if direct access is blocked, they can create a snapshot using create-db-snapshot. To exfiltrate this snapshot, they then use `modify-db-snapshot-attribute` to share it with their own AWS account. Once shared, they can copy it to their account and create a new, accessible database from it, effectively stealing the data.
6. Hardening AWS Security Groups and NACLs
Mitigation involves locking down network access to minimize the attack surface.
Verified Commands & Tutorials:
– `aws ec2 revoke-security-group-ingress –group-id
– `aws ec2 authorize-security-group-ingress –group-id
– `aws ec2 describe-network-acls` – Lists NACLs to review stateless inbound/outbound rules.
Step-by-Step Guide:
To remediate the initial exposure, security groups must be audited. The `revoke-security-group-ingress` command is used to remove overly permissive rules, such as allowing RDP/SSH from 0.0.0.0/0. It should be replaced with a principle of least privilege using authorize-security-group-ingress, specifying only the necessary corporate IP range. NACLs provide a second layer of defense and should be reviewed to ensure they are not allowing unrestricted traffic.
7. Implementing Proactive CSPM with Wiz CLI
Cloud Security Posture Management (CSPM) tools like Wiz can be integrated into CI/CD and command-line workflows for continuous monitoring.
Verified Commands & Tutorials:
– `wiz auth –id
– `wiz graphql “query { securityScans(first: 5) { nodes { id, status, createdAt } } }”` – Runs a custom GraphQL query to fetch recent security scans.
– `wiz issues list –severity HIGH –resource-type VM` – Lists all high-severity issues related to virtual machines.
– `wiz config create-rule –name “no-public-s3” –query ‘cloudProvider = “AWS” and resource.type = “BUCKET” and exposure.exposedToInternet = true’ –severity HIGH` – Creates a custom CSPM rule to detect publicly exposed S3 buckets.
Step-by-Step Guide:
Proactive security requires automation. After authenticating with wiz auth, a security engineer can use the `wiz issues list` command to programmatically pull a list of high-severity misconfigurations, such as publicly accessible S3 buckets or unrestricted security groups. For advanced use cases, the `wiz graphql` command allows for complex queries against the Wiz security graph. Furthermore, custom rules can be created with `wiz config create-rule` to enforce organizational policies, like automatically flagging any resource exposed to the internet.
What Undercode Say:
- The cloud shared responsibility model is often misunderstood, leading to a dangerous gap in security ownership where customer misconfigurations become the weakest link.
- Identity is the new perimeter; over-provisioned IAM roles represent a more significant risk than traditional network-level attacks.
The hands-on exercise with Wiz underscores a critical industry shift. The attack surface is no longer defined by a corporate firewall but by API endpoints, storage bucket policies, and identity roles. The techniques outlined, from IMDS exploitation to IAM privilege escalation, are not theoretical; they are the standard playbook for modern cloud attackers. The key insight is that reactive measures are insufficient. Security must be “shifting left” into the development and infrastructure-as-code lifecycle. Tools like CSPMs are essential for providing the continuous visibility and automated compliance checks needed to manage this complex, dynamic environment. Without this proactive posture, organizations are merely waiting for an attacker to discover their inevitable missteps.
Prediction:
The increasing automation of cloud attacks is the next frontier. We will see the rise of AI-driven penetration testing tools that can autonomously chain together misconfigurations and weak identities to compromise an entire cloud environment within minutes of discovery. Defensively, CSPM and Cloud Infrastructure Entitlement Management (CIEM) will become non-negotiable core security controls, deeply integrated with DevOps pipelines to enforce security policy as code before a single resource is ever provisioned. The future cloud security battle will be won or lost in the automation and speed of both attack and defense.
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IT/Security Reporter URL:
Reported By: Fmunozcano Seguridad – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
