Lack of protection against cookie tossing attacks in fastify-csrf

Vulnerability Description

fastify-csrf is an open-source plugin helps developers protect their Fastify server against CSRF attacks. Versions of fastify-csrf prior to 3.1.0 have a "double submit" mechanism using cookies with an application deployed across multiple subdomains, e.g. "heroku"-style platform as a service. Version 3.1.0 of the fastify-csrf fixes it. the vulnerability. The user of the module would need to supply a `userInfo` when generating the CSRF token to fully implement the protection on their end. This is needed only for applications hosted on different subdomains.

References

• https://github.com/fastify/fastify-csrf/security/advisories/GHSA-rc4q-9m69-gqp8
• https://github.com/fastify/csrf/pull/2
• https://github.com/fastify/fastify-csrf/pull/51
• https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html
• https://github.com/fastify/fastify-csrf/releases/tag/v3.1.0
• https://owasp.org/www-pdf-archive/David_Johansson-Double_Defeat_of_Double-Submit_Cookie.pdf