I was searching for history of XSS and CSRF attacks. I was mostly interested in knowing when each of these was discovered. I found following posts which tried to point out an approximate year of discoveries of these two vulnerabilities.
http://seclists.org/webappsec/2005/q4/0125.html
http://www.webappsec.org/lists/websecurity/archive/2005-05/msg00003.html
According to the first link, ("If I remember correctly, the term "Cross-Site Scripting" (or CSS at
the time) did originate around 1996-ish...
")
I.e. XSS was discovered on or before 1996.
Now take a look at the second one. According to it, the first CSRF was documented in May 2000!
But did it really take around 4 years for us to discover CSRF? I don't think so. First XSS might have been found accidentally. But when someone wanted to 'apply' it somewhere (whether for good reasons or bad), it was then that CSRF was discovered.
If I discover a XSS on www.mybank.com and I want to exploit my victim, I send him a link and he clicks on it. Now isn't this a kind of CSRF I'm carrying out? According to me, it is. Therefore I would go one step further and say that when the first client side attack discovered was to be launched, the attacker made use of CSRF.
It is true that CSRF can be exploited by more than one ways. You can have img srcs and all other techniques that make the browser send an additional request. CSRF may have different uses, e.g. transferring money from one account to other, but basic requirement is that you need to make your victim's browser send some requests to server without him knowing it. And thats what most XSS exploits do. Actual session riding will happen after login, but when there is XSS on post login pages, CSRF has to be there in order to successfully exploit it.
In general it is true that many of the web application attacks overlap with one another. Any other thoughts?