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We are aware of the recently disclosed PHP2Shell vulnerabilities (CVE-2026-109618 and CVE-2026-109619) and can confirm Filestack is not impacted by these vulnerabilities.

Multipart Upload

A multipart upload sends a file in several parts that are joined after they arrive. The Filestack SDKs use multipart uploads through the Filestack Upload API.

Storage

  • By default, multipart uploads are stored in Filestack’s Amazon S3 storage
  • With your own S3 bucket, parts go from the user’s device directly to your bucket
  • With other storage providers, files go to Filestack S3 first and are copied to your storage in the background. An upload webhook tells you when the copy is done.

Support

Multipart uploads are supported through the Filestack SDKs. Calls to the Upload API from other code are outside the Filestack SLA.

  • Intelligent Ingestion: resends failed parts in smaller pieces
  • Content Ingestion Network: receives parts at the nearest upload server

Documentation

Read the Filestack documentation page for this term.

Open the documentation