diff --git a/packages/backend/src/misc/download-url.ts b/packages/backend/src/misc/download-url.ts
index e9975f3486..83680c175f 100644
--- a/packages/backend/src/misc/download-url.ts
+++ b/packages/backend/src/misc/download-url.ts
@@ -92,7 +92,7 @@ export async function downloadUrl(url: string, path: string): Promise<void> {
 	logger.succ(`Download finished: ${chalk.cyan(url)}`);
 }
 
-function isPrivateIp(ip: string): boolean {
+export function isPrivateIp(ip: string): boolean {
 	for (const net of config.allowedPrivateNetworks || []) {
 		const cidr = new IPCIDR(net);
 		if (cidr.contains(ip)) {
diff --git a/packages/backend/src/services/drive/upload-from-url.ts b/packages/backend/src/services/drive/upload-from-url.ts
index 6e6059960f..abbefbbf6b 100644
--- a/packages/backend/src/services/drive/upload-from-url.ts
+++ b/packages/backend/src/services/drive/upload-from-url.ts
@@ -1,7 +1,7 @@
 import { URL } from "node:url";
 import type { User } from "@/models/entities/user.js";
 import { createTemp } from "@/misc/create-temp.js";
-import { downloadUrl } from "@/misc/download-url.js";
+import { downloadUrl, isPrivateIp } from "@/misc/download-url.js";
 import type { DriveFolder } from "@/models/entities/drive-folder.js";
 import type { DriveFile } from "@/models/entities/drive-file.js";
 import { DriveFiles } from "@/models/index.js";
@@ -23,10 +23,6 @@ type Args = {
 	requestHeaders?: Record<string, string> | null;
 };
 
-const PRIVATE_IPV4 =
-	/(^127\.)|(^10\.)|(^172\.1[6-9]\.)|(^172\.2[0-9]\.)|(^172\.3[0-1]\.)|(^192\.168\.)|(^0\.)/;
-const PRIVATE_IPV6 = /(f[c-e][0-9a-f][0-9a-f]:)|(F[C-E][0-9A-F][0-9A-F]:)|(::)/;
-
 export async function uploadFromUrl({
 	url,
 	user,
@@ -42,9 +38,7 @@ export async function uploadFromUrl({
 	const parsedUrl = new URL(url);
 	if (
 		process.env.NODE_ENV === "production" &&
-		(PRIVATE_IPV4.test(parsedUrl.hostname) ||
-			PRIVATE_IPV6.test(parsedUrl.hostname) ||
-			parsedUrl.hostname.includes("localhost"))
+		isPrivateIp(parsedUrl.hostname)
 	) {
 		throw new Error("Private IP is not allowed");
 	}