CVE-2023-29008 (published 2023-04-06T17:15Z)

The SvelteKit framework offers developers an option to create simple REST APIs. This is done by defining a `+server.js` file, containing endpoint handlers for different HTTP methods.\n\nSvelteKit provides out-of-the-box cross-site request forgery (CSRF) protection to its users. The protection is implemented at `kit/src/runtime/server/respond.js`. While the implementation does a sufficient job of mitigating common CSRF attacks, the protection can be bypassed in versions prior to 1.15.2 by simply specifying an upper-cased `Content-Type` header value. The browser will not send uppercase characters, but this check does not block all expected CORS requests.\n\nIf abused, this issue will allow malicious requests to be submitted from third-party domains, which can allow execution of operations within the context of the victim's session, and in extreme scenarios can lead to unauthorized access to users’ accounts. This may lead to all POST operations requiring authentication being allowed in the following cases: If the target site sets `SameSite=None` on its auth cookie and the user visits a malicious site in a Chromium-based browser; if the target site doesn't set the `SameSite` attribute explicitly and the user visits a malicious site with Firefox/Safari with tracking protections turned off; and/or if the user is visiting a malicious site with a very outdated browser.\n\nSvelteKit 1.15.2 contains a patch for this issue. It is also recommended to explicitly set `SameSite` to a value other than `None` on authentication cookies especially if the upgrade cannot be done in a timely manner.

CVSS v3 base score: 8.8, HIGH (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Weakness information:
cwe_id: CWE-352
cwe_name: Cross-Site Request Forgery (CSRF)
description: The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.
extended_description: When a web server is designed to receive a request from a client without any mechanism for verifying that it was intentionally sent, then it might be possible for an attacker to trick a client into making an unintentional request to the web server which will be treated as an authentic request. This can be done via a URL, image load, XMLHttpRequest, etc. and can result in exposure of data or unintended code execution.
         

Fix information:
repo_url: https://github.com/sveltejs/kit
commit_details: repo_url: https://github.com/sveltejs/kit
author: Ben McCann
author_date: 2023-04-06 08:45:55-07:00
msg: Merge pull request from GHSA-gv7g-x59x-wf8f

* fix: do a case-insensitive comparison when checking header value

* changeset

* remove export

* Update .changeset/happy-pots-move.md
repository: repo_url: https://github.com/sveltejs/kit
repo_name: sveltejs/kit
description: web development, streamlined
repo_language: JavaScript
owner: sveltejs
file_changes: filename: happy-pots-move.md
change_type: ModificationType.ADD
diff: @@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix: address security advisory CVE-2023-29008 by doing a case-insensitive comparison when checking header value

programming_language: SQL
filename: http.js
change_type: ModificationType.MODIFY
diff: @@ -59,9 +59,9 @@ export function negotiate(accept, types) {
  * @param {Request} request
  * @param  {...string} types
  */
-export function is_content_type(request, ...types) {
+function is_content_type(request, ...types) {
 	const type = request.headers.get('content-type')?.split(';', 1)[0].trim() ?? '';
-	return types.includes(type);
+	return types.includes(type.toLowerCase());
 }
 
 /**

programming_language: JavaScript
filename: server.test.js
change_type: ModificationType.MODIFY
diff: @@ -61,7 +61,8 @@ test.describe('CSRF', () => {
 		const content_types = [
 			'application/x-www-form-urlencoded',
 			'multipart/form-data',
-			'text/plain'
+			'text/plain',
+			'text/plaiN'
 		];
 		const methods = ['POST', 'PUT', 'PATCH', 'DELETE'];
 		for (const method of methods) {

programming_language: TypeScript