Cross-site Scripting (XSS) Affecting angular Open this link in a new tab package, versions <1.6.7

angular is a package that lets you write client-side web applications as if you had a smarter browser. It also lets you use HTML as your template language and lets you extend HTML’s syntax to express your application’s components clearly and succinctly.

Affected versions of this package are vulnerable to Cross-site Scripting (XSS). Browsers mutate attributes values such as 　javascript:alert(1) when they are written to the DOM via innerHTML in various vendor specific ways. In Chrome (<62), this mutation removed the preceding "whitespace" resulting in a value that could end up being executed as JavaScript.

Here is an example of what could happen:

// Code goes here
var h1 = document.querySelector('h1');
h1.innerHTML = '<a href="&#x3000;javascript:alert(1)">CLICKME</a>';
var innerHTML = h1.innerHTML;
console.log(innerHTML);
h1.innerHTML = innerHTML;

The sanitizer contains a bit of code that triggers this mutation on an inert piece of DOM, before angular sanitizes it.

Note: Chrome 62 does not appear to mutate this particular string any more, instead it just leaves the "whitespace" in place. This probably means that Chrome 62 is no longer vulnerable to this specific attack vector.

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