Payload: Client uploads could overwrite S3 objects

Description

An authenticated user could overwrite an existing S3 object belonging to another upload collection, bypassing that collection’s access controls and prior file validation.

You are affected if ALL of these are true:

• Client uploads are enabled for multiple collections that share an S3 bucket.

Recommendation

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

• Affected version(s): **>= 4.0.0-canary.0, < 4.0.0-canary.34

  < 3.90.0**

• Patched version(s): **4.0.0-canary.34

  3.90.0**

References

• GHSA-7vg8-29qx-jgj8
• CVE-2026-105867
• CWE-639
• CAPEC-310