Could a CSRF attack have any direct way of accessing or manipulating its target site's javascript variables?

Does it open any attack vector if an ajax-driven sit开发者_如何学JAVAe uses a unique token stored as a javascript variable and verifies it with every request to prevent CSRF -- provided that the site is free from XSS holes?

It doesn't open it up to attack. If the site is free from XSS holes, there is no way another page could get the token from a javascript variable.