Introduction
It is recommended to use uniform bucket-level access to unify and simplify how you grant access to your Cloud Storage resources. Cloud Storage offers two systems for granting users permission to access your buckets and objects: Cloud Identity and Access Management (Cloud IAM) and Access Control Lists (ACLs). These systems act in parallel - in order for a user to access a Cloud Storage resource, only one of the systems needs to grant the user permission. Cloud IAM is used throughout Google Cloud and allows you to grant a variety of permissions at the bucket and project levels. ACLs are used only by Cloud Storage and have limited permission options, but they allow you to grant permissions on a per-object basis.
In order to support a uniform permissioning system, Cloud Storage has uniform bucket-level access. Using this feature disables ACLs for all Cloud Storage resources: access to Cloud Storage resources then is granted exclusively through Cloud IAM. Enabling uniform bucket-level access guarantees that if a Storage bucket is not publicly accessible, no object in the bucket is publicly accessible either.
Steps to enable uniform Bucket-level Access for Bucket using CLI
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To list the buckets run the below command
gcloud storage ls
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Use the
on
option in auniformbucketlevelaccess
set command:gsutil uniformbucketlevelaccess set on gs://<bucket_name>/
Specify the name of the bucket on which this misconfiguration is applicable
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To check if uniformbucketlevelaccess is enabled or not run the below command
gsutil uniformbucketlevelaccess get gs://<bucket_name>

Riyaz Walikar
Founder & Chief of R&D
Riyaz is the founder and Chief of R&D at Kloudle, where he hunts for cloud misconfigurations so developers don’t have to. With over 15 years of experience breaking into systems, he’s led offensive security at PwC and product security across APAC for Citrix. Riyaz created the Kubernetes security testing methodology at Appsecco, blending frameworks like MITRE ATT&CK, OWASP, and PTES. He’s passionate about teaching people how to hack—and how to stay secure.

Riyaz Walikar
Founder & Chief of R&D
Riyaz is the founder and Chief of R&D at Kloudle, where he hunts for cloud misconfigurations so developers don’t have to. With over 15 years of experience breaking into systems, he’s led offensive security at PwC and product security across APAC for Citrix. Riyaz created the Kubernetes security testing methodology at Appsecco, blending frameworks like MITRE ATT&CK, OWASP, and PTES. He’s passionate about teaching people how to hack—and how to stay secure.