When HttpOnly flag is used, JavaScript will not be able to read the cookie in case of XSS exploitation. It was also presented how the combination of HTTP TRACE method and XSS might be used to bypass HttpOnly flag – this combination is cross-site tracing (XST) attack. It turns out that modern browsers block the HTTP TRACE method in XMLHttpRequest. However, it’s still important to know how XST works. If the attacker finds another way of sending HTTP TRACE, then he can bypass an HttpOnly flag when he understands how XST works.