Directus's S3 assets become unavailable after a burst of HEAD requests
Date: 2025-03
Affected: npm/directus, npm/@directus/storage-driver-s3
Attack vector: dos
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2025-30350
CWE: CWE-770
CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

### Summary There's some tools that use Directus to sync content and assets. Some of those tools use HEAD method, like Shopify, to check the existence of files. Although, when making many HEAD requests at once, at some point, all assets are being served as 403. ### Details When I was investigating this issue, I have found that after the burst of HEAD requests, the amount of `sockets` held on [Agent on NodeHttpHandler](https://github.com/smithy-lang/smithy-typescript/blob/main/packages/node-http-handler/src/node-http-handler.ts#L189) was always equal to [`STORAGE_CLOUD_MAX_SOCKETS`](https://github.com/directus/directus/blob/main/packages/storage-driver-s3/src/index.ts#L89) making it impossible to have new connections causing assets to be inaccessible. After looking into this [issue on AWS SDK](https://github.com/aws/aws-sdk-js-v3/issues/6691) I found that if the [stream is requested](https://github.com/directus/directus/blob/main/api/src/services/assets.ts#L213), it needs to be consumed otherwise will hang forever. And as can be [seen here](https://github.com/directus/directus/blob/main/api/src/controllers/assets.ts#L233-L238) the stream is not consumed. The [timeouts set here](https://github.com/directus/directus/blob/main/packages/storage-driver-s3/src/index.ts#L87-L88) had no noticeable effect on tests made. ### PoC This can be easily reproduced with the following steps: - setup AWS S3 storage - set STORAGE_CLOUD_MAX_SOCKETS: "50" (this value is lower than default for


Mitigations:

Architectural layers (MAESTRO):