This is a tale of cookies, Internet code and a CVE. It goes back a long time so please take a seat, lean back and follow along.
The scene is of course curl, the internet transfer tool and library I work on.
1998
In October 1998 we shipped curl 4.9. In 1998. Few people had heard of curl or used it back then. This was a few months before the curl website would announce that curl achieved 300 downloads of a new release. curl was still small in every meaning of the word at that time.
curl 4.9 was the first release that shipped with the “cookie engine”. curl could then receive HTTP cookies, parse them, understand them and send back cookies properly in subsequent requests. Like the browsers did. I wrote the bigger part of the curl code for managing cookies.
In 1998, the only specification that existed and described how cookies worked was a very brief document that Netscape used to host called cookie_spec. I keep a copy of that document around for curious readers. It really does not document things very well and it leaves out enormous amounts information that you had to figure out by inspecting other clients.
The cookie code I implemented than was based on that documentation and what the browsers seemed to do at the time. It seemed to work with numerous server implementations. People found good use for the feature.
2000s
This decade passed with a few separate efforts in the IETF to create cookie specifications but they all failed. The authors of these early cookie specs probably thought they could create standards and the world would magically adapt to them, but this did not work. Cookies are somewhat special in the regard that they are implemented by so many different authors, code bases and websites that fundamentally changing the way they work in a “decree from above” like that is difficult if not downright impossible.
RFC 6265
Finally, in 2011 there was a cookie rfc published! This time with the reversed approach: it primarily documented and clarified how cookies were actually already being used.
I was there and I helped it get made by proving my views and opinions. I did not agree to everything that the spec includes (you can find blog posts about some of those details), but finally having a proper spec was still a huge improvement to the previous state of the world.