backpack/crud provides Create, Read, Update & Delete (CRUD) functions for Backpack, a collection of Laravel packages that help users build custom administration panels. From 6.0.0 until 6.8.15 and 7.0.47, HasMany and MorphMany handling through attachManyRelation during CRUD create and update operations accepts submitted child primary keys without consistently restricting updates to records belonging to the current parent or permitted by the developer-defined relation scope. An authenticated low-privilege administrator who can edit a parent form exposing an affected multiple-relation field can cause unrelated child records to be reassigned, detached, nulled, or deleted across ownership or tenant boundaries. Exploitation requires related records that should not be attachable or removable by that administrator and the absence of additional application-level authorization around submitted relation values. This issue is distinct from earlier direct main-entity CRUD scoping fixes because it affects secondary models modified by relationship-saving logic. This issue is fixed in versions 6.8.15 and 7.0.47.

Affected: Packagist: backpack/crud

## Vulnerability Details

Affected area: HasMany / MorphMany relation handling during CRUD create and update operations CWE: CWE-862 — Missing Authorization Severity: Medium CVSS: 6.5 — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

### Summary

Backpack CRUD contained an authorization issue in the way certain HasMany and MorphMany relationship fields were processed during create and update operations.

When an admin form allowed users to manage multiple related records, Backpack could update related model records based on submitted primary keys without sufficiently checking whether those records were eligible to be associated with the current parent model.

This could allow an authenticated, low-privileged admin user to affect related records outside the intended authorization or tenancy boundary, if the affected CRUD form exposed this type of relationship field.

### Root Cause

The vulnerable logic processed submitted relationship values and updated matching related records without consistently limiting those updates to records that already belonged to the current parent model, or to records allowed by the developer-defined relation scope.

As a result, a user with permission to edit one parent record could potentially cause unrelated child records to be reassigned, detached, nulled, or deleted as a side effect of saving the form.

This issue is separate from earlier fixes that scoped direct CRUD operations on the main entity. Those protections covered the model bein…