diff --git a/docs/pages/guides/email-and-password/basics.md b/docs/pages/guides/email-and-password/basics.md
index 7f3bada46..0631a2734 100644
--- a/docs/pages/guides/email-and-password/basics.md
+++ b/docs/pages/guides/email-and-password/basics.md
@@ -148,7 +148,16 @@ app.post("/login", async (request: Request) => {
 	const user = await db.table("user").where("email", "=", email).get();
 
 	if (!user) {
-		// invalid email
+		// NOTE:
+		// Returning immediately allows malicious actors to figure out valid emails from response times,
+		// allowing them to only focus on guessing passwords in brute-force attacks.
+		// As a preventive measure, you may want to hash passwords even for invalid emails.
+		// However, valid emails can be already be revealed with the signup page
+		// and a similar timing issue can likely be found in password reset implementation.
+		// It will also be much more resource intensive.
+		// Since protecting against this is none-trivial,
+		// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+		// If emails/usernames are public, you may outright tell the user that the username is invalid.
 		return new Response("Invalid email or password", {
 			status: 400
 		});
diff --git a/docs/pages/guides/validate-session-cookies/astro.md b/docs/pages/guides/validate-session-cookies/astro.md
index b361b57df..967da98a2 100644
--- a/docs/pages/guides/validate-session-cookies/astro.md
+++ b/docs/pages/guides/validate-session-cookies/astro.md
@@ -17,7 +17,8 @@ import { defineMiddleware } from "astro:middleware";
 export const onRequest = defineMiddleware(async (context, next) => {
 	if (context.request.method !== "GET") {
 		const originHeader = request.headers.get("Origin");
-		const hostHeader = request.headers.get("Header");
+		// NOTE: You may need to use `X-Forwarded-Host` instead
+		const hostHeader = request.headers.get("Host");
 		if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 			return new Response(null, {
 				status: 403
diff --git a/docs/pages/guides/validate-session-cookies/elysia.md b/docs/pages/guides/validate-session-cookies/elysia.md
index 39f89ed60..83aa12567 100644
--- a/docs/pages/guides/validate-session-cookies/elysia.md
+++ b/docs/pages/guides/validate-session-cookies/elysia.md
@@ -24,6 +24,7 @@ const app = new Elysia().derive(
 		// CSRF check
 		if (context.request.method !== "GET") {
 			const originHeader = context.request.headers.get("Origin");
+			// NOTE: You may need to use `X-Forwarded-Host` instead
 			const hostHeader = context.request.headers.get("Host");
 			if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 				return {
diff --git a/docs/pages/guides/validate-session-cookies/express.md b/docs/pages/guides/validate-session-cookies/express.md
index 0f2c2fbef..85b736942 100644
--- a/docs/pages/guides/validate-session-cookies/express.md
+++ b/docs/pages/guides/validate-session-cookies/express.md
@@ -20,6 +20,7 @@ app.use((req, res, next) => {
 		return next();
 	}
 	const originHeader = req.headers.origin ?? null;
+	// NOTE: You may need to use `X-Forwarded-Host` instead
 	const hostHeader = req.headers.host ?? null;
 	if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 		return res.status(403).end();
diff --git a/docs/pages/guides/validate-session-cookies/hono.md b/docs/pages/guides/validate-session-cookies/hono.md
index 64f83680a..809103ae4 100644
--- a/docs/pages/guides/validate-session-cookies/hono.md
+++ b/docs/pages/guides/validate-session-cookies/hono.md
@@ -28,6 +28,7 @@ app.use("*", (c, next) => {
 		return next();
 	}
 	const originHeader = c.req.headers.get("Origin");
+	// NOTE: You may need to use `X-Forwarded-Host` instead
 	const hostHeader = c.req.headers.get("Host");
 	if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 		return c.body(null, 403);
diff --git a/docs/pages/guides/validate-session-cookies/index.md b/docs/pages/guides/validate-session-cookies/index.md
index 540f7a01c..6e2ce8202 100644
--- a/docs/pages/guides/validate-session-cookies/index.md
+++ b/docs/pages/guides/validate-session-cookies/index.md
@@ -16,15 +16,16 @@ This guide is also available for:
 - [SolidStart](/guides/validate-session-cookies/solidstart)
 - [SvelteKit](/guides/validate-session-cookies/sveltekit)
 
-**CSRF protection must be implemented when using cookies and forms.** This can be easily done by comparing the `Origin` and `Host` header.
+**CSRF protection must be implemented when using cookies and forms.** This can be easily done by comparing the `Origin` and `Host` header. 
 
 For non-GET requests, check the request origin. You can use `readSessionCookie()` to get the session cookie from a HTTP `Cookie` header, and validate it with `Lucia.validateSession()`. Make sure to delete the session cookie if it's invalid and create a new session cookie when the expiration gets extended, which is indicated by `Session.fresh`.
 
 ```ts
 import { verifyRequestOrigin } from "lucia";
 
-// only required in non-GET requests (POST, PUT, DELETE, PATCH, etc)
+// Only required in non-GET requests (POST, PUT, DELETE, PATCH, etc)
 const originHeader = request.headers.get("Origin");
+// NOTE: You may need to use `X-Forwarded-Host` instead
 const hostHeader = request.headers.get("Host");
 if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 	return new Response(null, {
diff --git a/docs/pages/guides/validate-session-cookies/nextjs-app.md b/docs/pages/guides/validate-session-cookies/nextjs-app.md
index 351d944a6..472678fd5 100644
--- a/docs/pages/guides/validate-session-cookies/nextjs-app.md
+++ b/docs/pages/guides/validate-session-cookies/nextjs-app.md
@@ -87,6 +87,7 @@ export async function middleware(request: NextRequest): Promise<NextResponse> {
 		return NextResponse.next();
 	}
 	const originHeader = request.headers.get("Origin");
+	// NOTE: You may need to use `X-Forwarded-Host` instead
 	const hostHeader = request.headers.get("Host");
 	if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 		return new NextResponse(null, {
diff --git a/docs/pages/guides/validate-session-cookies/nextjs-pages.md b/docs/pages/guides/validate-session-cookies/nextjs-pages.md
index bef44cb9c..5d5af47b4 100644
--- a/docs/pages/guides/validate-session-cookies/nextjs-pages.md
+++ b/docs/pages/guides/validate-session-cookies/nextjs-pages.md
@@ -17,6 +17,7 @@ export async function middleware(request: NextRequest): Promise<NextResponse> {
 		return NextResponse.next();
 	}
 	const originHeader = request.headers.get("Origin");
+	// NOTE: You may need to use `X-Forwarded-Host` instead
 	const hostHeader = request.headers.get("Host");
 	if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 		return new NextResponse(null, {
diff --git a/docs/pages/guides/validate-session-cookies/nuxt.md b/docs/pages/guides/validate-session-cookies/nuxt.md
index 173a26129..9547bd803 100644
--- a/docs/pages/guides/validate-session-cookies/nuxt.md
+++ b/docs/pages/guides/validate-session-cookies/nuxt.md
@@ -17,6 +17,7 @@ import type { Session, User } from "lucia";
 export default defineEventHandler(async (event) => {
 	if (event.method !== "GET") {
 		const originHeader = getHeader(event, "Origin") ?? null;
+		// NOTE: You may need to use `X-Forwarded-Host` instead
 		const hostHeader = getHeader(event, "Host") ?? null;
 		if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 			return event.node.res.writeHead(403).end();
diff --git a/docs/pages/guides/validate-session-cookies/solidstart.md b/docs/pages/guides/validate-session-cookies/solidstart.md
index 1ae6d5d14..f59be02a7 100644
--- a/docs/pages/guides/validate-session-cookies/solidstart.md
+++ b/docs/pages/guides/validate-session-cookies/solidstart.md
@@ -17,6 +17,7 @@ import { lucia } from "./lib/auth";
 export default defineEventHandler((event) => {
 	if (context.request.method !== "GET") {
 		const originHeader = getHeader(event, "Origin") ?? null;
+		// NOTE: You may need to use `X-Forwarded-Host` instead
 		const hostHeader = getHeader(event, "Host") ?? null;
 		if (!originHeader || !hostHeader || !verifyRequestOrigin(originHeader, [hostHeader])) {
 			return event.node.res.writeHead(403).end();
diff --git a/docs/pages/tutorials/username-and-password/astro.md b/docs/pages/tutorials/username-and-password/astro.md
index 07d11090d..06de5fb89 100644
--- a/docs/pages/tutorials/username-and-password/astro.md
+++ b/docs/pages/tutorials/username-and-password/astro.md
@@ -190,6 +190,15 @@ export async function POST(context: APIContext): Promise<Response> {
 		.where("username", "=", username.toLowerCase())
 		.get();
 	if (!existingUser) {
+		// NOTE:
+		// Returning immediately allows malicious actors to figure out valid usernames from response times,
+		// allowing them to only focus on guessing passwords in brute-force attacks.
+		// As a preventive measure, you may want to hash passwords even for invalid usernames.
+		// However, valid usernames can be already be revealed with the signup page among other methods.
+		// It will also be much more resource intensive.
+		// Since protecting against this is none-trivial,
+		// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+		// If usernames are public, you may outright tell the user that the username is invalid.
 		return new Response("Incorrect username or password", {
 			status: 400
 		});
diff --git a/docs/pages/tutorials/username-and-password/nextjs-app.md b/docs/pages/tutorials/username-and-password/nextjs-app.md
index 5964e557b..fc4c9239d 100644
--- a/docs/pages/tutorials/username-and-password/nextjs-app.md
+++ b/docs/pages/tutorials/username-and-password/nextjs-app.md
@@ -212,6 +212,15 @@ async function login(_: any, formData: FormData): Promise<ActionResult> {
 		.where("username", "=", username.toLowerCase())
 		.get();
 	if (!existingUser) {
+		// NOTE:
+		// Returning immediately allows malicious actors to figure out valid usernames from response times,
+		// allowing them to only focus on guessing passwords in brute-force attacks.
+		// As a preventive measure, you may want to hash passwords even for invalid usernames.
+		// However, valid usernames can be already be revealed with the signup page among other methods.
+		// It will also be much more resource intensive.
+		// Since protecting against this is none-trivial,
+		// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+		// If usernames are public, you may outright tell the user that the username is invalid.
 		return {
 			error: "Incorrect username or password"
 		};
diff --git a/docs/pages/tutorials/username-and-password/nextjs-pages.md b/docs/pages/tutorials/username-and-password/nextjs-pages.md
index c488b98fd..dc0db6088 100644
--- a/docs/pages/tutorials/username-and-password/nextjs-pages.md
+++ b/docs/pages/tutorials/username-and-password/nextjs-pages.md
@@ -240,6 +240,15 @@ export default async function handler(req: NextApiRequest, res: NextApiResponse)
 		.where("username", "=", username.toLowerCase())
 		.get();
 	if (!existingUser) {
+		// NOTE:
+		// Returning immediately allows malicious actors to figure out valid usernames from response times,
+		// allowing them to only focus on guessing passwords in brute-force attacks.
+		// As a preventive measure, you may want to hash passwords even for invalid usernames.
+		// However, valid usernames can be already be revealed with the signup page among other methods.
+		// It will also be much more resource intensive.
+		// Since protecting against this is none-trivial,
+		// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+		// If usernames are public, you may outright tell the user that the username is invalid.
 		res.status(400).json({
 			error: "Incorrect username or password"
 		});
diff --git a/docs/pages/tutorials/username-and-password/nuxt.md b/docs/pages/tutorials/username-and-password/nuxt.md
index 4618ea4d8..b93e63fbe 100644
--- a/docs/pages/tutorials/username-and-password/nuxt.md
+++ b/docs/pages/tutorials/username-and-password/nuxt.md
@@ -209,6 +209,15 @@ export default eventHandler(async (event) => {
 		.where("username", "=", username.toLowerCase())
 		.get();
 	if (!existingUser) {
+		// NOTE:
+		// Returning immediately allows malicious actors to figure out valid usernames from response times,
+		// allowing them to only focus on guessing passwords in brute-force attacks.
+		// As a preventive measure, you may want to hash passwords even for invalid usernames.
+		// However, valid usernames can be already be revealed with the signup page among other methods.
+		// It will also be much more resource intensive.
+		// Since protecting against this is none-trivial,
+		// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+		// If usernames are public, you may outright tell the user that the username is invalid.
 		throw createError({
 			message: "Incorrect username or password",
 			statusCode: 400
diff --git a/docs/pages/tutorials/username-and-password/sveltekit.md b/docs/pages/tutorials/username-and-password/sveltekit.md
index 64ac9ae40..278bc8d55 100644
--- a/docs/pages/tutorials/username-and-password/sveltekit.md
+++ b/docs/pages/tutorials/username-and-password/sveltekit.md
@@ -123,7 +123,7 @@ export const actions: Actions = {
 			...sessionCookie.attributes
 		});
 
-		 redirect(302, "/");
+		redirect(302, "/");
 	}
 };
 ```
@@ -198,6 +198,15 @@ export const actions: Actions = {
 			.where("username", "=", username.toLowerCase())
 			.get();
 		if (!existingUser) {
+			// NOTE:
+			// Returning immediately allows malicious actors to figure out valid usernames from response times,
+			// allowing them to only focus on guessing passwords in brute-force attacks.
+			// As a preventive measure, you may want to hash passwords even for invalid usernames.
+			// However, valid usernames can be already be revealed with the signup page among other methods.
+			// It will also be much more resource intensive.
+			// Since protecting against this is none-trivial,
+			// it is crucial your implementation is protected against brute-force attacks with login throttling etc.
+			// If usernames are public, you may outright tell the user that the username is invalid.
 			return fail(400, {
 				message: "Incorrect username or password"
 			});
@@ -217,7 +226,7 @@ export const actions: Actions = {
 			...sessionCookie.attributes
 		});
 
-		 redirect(302, "/");
+		redirect(302, "/");
 	}
 };
 ```
@@ -231,7 +240,7 @@ You can validate requests by checking `locals.user`. The field `user.username` i
 import type { PageServerLoad, Actions } from "./$types";
 
 export const load: PageServerLoad = async (event) => {
-	if (!event.locals.user)  redirect(302, "/login");
+	if (!event.locals.user) redirect(302, "/login");
 	return {
 		username: event.locals.user.username
 	};
@@ -264,7 +273,7 @@ export const actions: Actions = {
 			path: ".",
 			...sessionCookie.attributes
 		});
-		 redirect(302, "/login");
+		redirect(302, "/login");
 	}
 };
 ```