Language: JavaScript
Label: safe
CWE: CWE-352 \u2014 Cross-Site Request Forgery (CSRF)
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.

Code:
function backToPurchaseList() {
    
    /** show the customer purchase list */
    $("#showPurchaseList").show();

    /** Hide the purchase product list */
    $("#showPurchaseProductList").hide();

}