window.onmessage = event => { // OK - good origin check let origin = event.origin.toLowerCase(); if (origin !== window.location.origin) { return; } eval(event.data); } window.onmessage = event => { // $ Alert - no origin check let origin = event.origin.toLowerCase(); console.log(origin); eval(event.data); } window.onmessage = event => { // OK - there is an origin check if (event.origin === "https://www.example.com") { // do something } } self.onmessage = function(e) { // $ Alert Commands[e.data.cmd].apply(null, e.data.args); }; window.onmessage = event => { // OK - there is an origin check if (mySet.includes(event.origin)) { // do something } } window.onmessage = event => { // OK - there is an origin check if (mySet.includes(event.source)) { // do something } } self.onmessage = function(e) { // $ Alert Commands[e.data.cmd].apply(null, e.data.args); }; window.addEventListener('message', function(e) { // OK - has a good origin check if (is_sysend_post_message(e) && is_valid_origin(e.origin)) { var payload = JSON.parse(e.data); if (payload && payload.name === uniq_prefix) { var data = unserialize(payload.data); sysend.broadcast(payload.key, data); } } }); function is_valid_origin(origin) { if (!domains) { warn("no domains configured"); return true; } var valid = domains.includes(origin); if (!valid) { warn("invalid origin: " + origin); } return valid; } window.onmessage = event => { // OK - the check is OK if ("https://www.example.com".startsWith(event.origin)) { // do something } }