Astro is a web framework for content-driven websites. A bug in the build process allows any unauthenticated user to read parts of the server source code. During build, along with client assets such as css and font files, the sourcemap files **for the server code** are moved to a publicly-accessible folder. Any outside party can read them with an unauthorized HTTP GET request to the same server hosting the rest of the website. While some server files are hashed, making their access obscure, the files corresponding to the file system router (those in `src/pages`) are predictably named. For example. the sourcemap file for `src/pages/index.astro` gets named `dist/client/pages/index.astro.mjs.map`. This vulnerability is the root cause of issue #12703, which links to a simple stackblitz project demonstrating the vulnerability. Upon build, notice the contents of the `dist/client` (referred to as `config.build.client` in astro code) folder. All astro servers make the folder in question access…

Astro is a web framework for content-driven websites. In affected versions a bug in Astro’s CSRF-protection middleware allows requests to bypass CSRF checks. When the `security.checkOrigin` configuration option is set to `true`, Astro middleware will perform a CSRF check. However, a vulnerability exists that can bypass this security. A semicolon-delimited parameter is allowed after the type in `Content-Type`. Web browsers will treat a `Content-Type` such as `application/x-www-form-urlencoded; abc` as a `simple request` and will not perform preflight validation. In this case, CSRF is not blocked as expected. Additionally, the `Content-Type` header is not required for a request. This issue has been addressed in version 4.16.17 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

The Astro web framework has a DOM Clobbering gadget in the client-side router starting in version 3.0.0 and prior to version 4.16.1. It can lead to cross-site scripting (XSS) in websites enables Astro's client-side routing and has *stored* attacker-controlled scriptless HTML elements (i.e., `iframe` tags with unsanitized `name` attributes) on the destination pages. This vulnerability can result in cross-site scripting (XSS) attacks on websites that built with Astro that enable the client-side routing with `ViewTransitions` and store the user-inserted scriptless HTML tags without properly sanitizing the `name` attributes on the page. Version 4.16.1 contains a patch for this issue.