Default swagger-ui configuration exposes all files in the module

fastify-swagger-ui is a Fastify plugin for serving Swagger UI. Prior to 2.1.0, the default configuration of `@fastify/swagger-ui` without `baseDir` set will lead to all files in the module's directory being exposed via http routes served by the module. The vulnerability is fixed in v2.1.0. Setting the `baseDir` option can also work around this vulnerability.

A Cascading Style Sheets (CSS) injection vulnerability in Swagger UI before 3.23.11 allows attackers to use the Relative Path Overwrite (RPO) technique to perform CSS-based input field value exfiltration, such as exfiltration of a CSRF token value. In other words, this product intentionally allows the embedding of untrusted JSON data from remote servers, but it was not previously known that <style>@import within the JSON data was a functional attack method.

Swagger UI 4.1.2 and earlier could allow a remote attacker to conduct spoofing attacks. By persuading a victim to open a crafted URL, an attacker could exploit this vulnerability to display remote OpenAPI definitions. Note: This was originally claimed to be resolved in 4.1.3. However, third parties have indicated this is not resolved in 4.1.3 and even occurs in that version and possibly others.