Ermetic Releases Open Source Tool to Automatically Troubleshoot AccessDenied Errors on AWS
March 24, 2022
Ermetic announced it has released a free open source tool for managing AccessDenied Events in Amazon Web Services (AWS) that automates time consuming cloud access policy troubleshooting and correction. Access Undenied on AWS analyzes AWS CloudTrail AccessDenied events, scans the environment to identify and explain the reasons for the events, and offers actionable least-privilege remediation suggestions.
The project is led by Noam Daham, research lead at Ermetic. You can read his blog introducing the tool here.
“Even if you know the policy type causing ‘access denied’, which isn’t always the case, you still need to find the policy and the statement inside the policy causing the denial, and replace it with a least-privilege alternative,” Noam Dahan. “Basically, you give the Access Undenied on AWS tool a CloudTrail event with an “Access Denied” outcome, and it will tell you how to fix it!”
Access Undenied on AWS addresses some of the peskiest Access Denied challenges encountered by DevOps and security teams on a daily basis, including:
Some AccessDenied messages still do not provide details. Among the services for which some, or even many, messages are lacking in detail are: S3, IAM, STS, CloudWatch, EFS, DynamoDB, Redshift, Opensearch and ACM.
When the reason for AccessDenied is an explicit deny, users can have difficulty tracking down the specific policy and statement that generated the explicit deny. Specifically, when the reason is an explicit deny in a service control policy (SCP), it is difficult to find and assess every single policy in the organization that applies to the account.
Meanwhile, when the problem is a missing allow statement, it can still be challenging to create the least-privilege policy that allows the desired access without granting excessive permissions.
Access Undenied on AWS is available here, and supports policies for many resources and some of the most common condition keys. This open source project is also soliciting input from the community through contributions of new issues in the repository.