> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/appsec-rules/iac-security/public-exposure/appsec-gcp-99.md).

# GCP Pub/Sub Topics are anonymously or publicly accessible misconfiguration detected in code

## Rule Details

|                        |                        |
| ---------------------- | ---------------------- |
| Cortex AppSec Rule ID  | APPSEC\_GCP\_99        |
| Category - Subcategory | Public Exposure - APIs |
| Provider               | GCP                    |
| Severity               | MEDIUM                 |
| Framework              | Terraform              |

## Impact

Pub/Sub is commonly used for asynchronous communication for applications in GCP. Messages are published to a *Pub/Sub Topic* and the ability to publish a message is controlled via IAM policies. It is possible to make *Pub/Sub Topics* publicly or anonymously accessible. Public notification topics can expose sensitive data and are a target for data exfiltration. We recommend you ensure that neither anonymous or public access to *Pub/Sub Topics* is allowed.

## How to Fix

*Resource:* google\_pubsub\_topic\_iam\_binding

* *Field:* members
* *Resource:* google\_pubsub\_topic\_iam\_member
* *Field:* member \[source,go]

***

resource "google\_pubsub\_topic\_iam\_binding" "public\_binding" { topic = google\_pubsub\_topic.example.name role = "roles/pubsub.publisher"

members = \[

* "allUsers",
* "allAuthenticatedUsers", ] }

***

resource "google\_pubsub\_topic\_iam\_member" "public\_member" { topic = google\_pubsub\_topic.example.name role = "roles/pubsub.publisher"

* member = "allUsers"
* member = "allAuthenticatedUsers" }

***


---

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