Tandoor Recipes is an application for managing recipes, planning meals, and building shopping lists. Prior to 2.6.4, the PUT /api/recipe/batch_update/ endpoint in Tandoor Recipes allows any authenticated user within a Space to modify any recipe in that Space, including recipes marked as private by other users. This bypasses all object-level authorization checks enforced on standard single-recipe endpoints (PUT /api/recipe/{id}/), enabling forced exposure of private recipes, unauthorized self-grant of access via the shared list, and metadata tampering. This vulnerability is fixed in 2.6.4.