CVE-2026-54329: Snipe-IT API Vulnerable to Cross-Tenant Accessory Injection

A cross-tenant data injection vulnerability was identified in the Snipe-IT Accessories API when Full Multiple Companies Support (FMCS) is enabled. A low-privileged authenticated user belonging to one company can create an accessory record under another company by supplying a foreign company_id value in the API request body.

The issue occurs because the API create path mass-assigns request parameters directly to the Accessory model, and the Accessory model allows company_id to be mass assigned. Unlike the web controller, which uses Company::getIdForCurrentUser() to enforce the authenticated user’s company context, the API controller does not apply equivalent tenant enforcement during accessory creation.

As a result, a Company A user can inject persistent accessory records into Company B. The injected records are then visible to Company B users as legitimate Company B inventory records. This breaks the integrity of company-scoped inventory data and represents a tenant isolation failure in the accessory creation flow.