Vulnerability library
Security checkMarch 12, 2026

StudioCMS S3 Storage Manager Authorization Bypass via Missing `await` on Async Auth Check

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Description

The S3 storage manager’s isAuthorized() function is declared async (returns Promise<boolean>) but is called without await in both the POST and PUT handlers. Since a Promise object is always truthy in JavaScript, !isAuthorized(type) always evaluates to false, completely bypassing the authorization check.

Recommendation

Update the @studiocms/s3-storage package to the latest compatible version. Followings are version details:

  • Affected version(s): <= 0.3.0
  • Patched version(s): 0.3.1

References

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Related Issues

See something that needs correcting? Let us knowUpdated March 12, 2026