Payload: Field-level write access bypass in Payload on MongoDB

### Impact A vulnerability in field-level access control could allow an authenticated user to modify fields they are not permitted to change on documents they can otherwise update. You are affected if: Payload version < `3.87.0` (or a `4.0.0-canary` release before `4.0.0-canary.20`) using the MongoDB adapter (`@payloadcms/db-mongodb`) with any collection that relies on field-level access control to restrict writes under certain conditions. Relational adapters (Postgres, SQLite) are not affected. ### Patches Handling of incoming field data has been hardened so field-level access control is enforced consistently. Users should upgrade to `3.87.0` (or `4.0.0-canary.20` on the `4.x` line) or later. ### Workarounds There is no complete workaround. Upgrading to `3.87.0` (or `4.0.0-canary.20` on the `4.x` line) is recommended.

Source published

7 Oct 2026 16:19:57 UTC

Source modified

7 Oct 2026 16:30:06 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N

Publisher rating · HIGH