diff --git a/src/vs/code/electron-main/app.ts b/src/vs/code/electron-main/app.ts
index ac970624ec8..74cd460f5e3 100644
--- a/src/vs/code/electron-main/app.ts
+++ b/src/vs/code/electron-main/app.ts
@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { app, ipcMain as ipc, systemPreferences, shell, Event, contentTracing, protocol, powerMonitor, IpcMainEvent, BrowserWindow } from 'electron';
+import { app, ipcMain as ipc, systemPreferences, shell, Event, contentTracing, protocol, powerMonitor, IpcMainEvent, BrowserWindow, dialog } from 'electron';
 import { IProcessEnvironment, isWindows, isMacintosh } from 'vs/base/common/platform';
 import { WindowsMainService } from 'vs/platform/windows/electron-main/windowsMainService';
 import { IWindowOpenable } from 'vs/platform/windows/common/windows';
@@ -80,6 +80,7 @@ import { coalesce } from 'vs/base/common/arrays';
 import { IStorageKeysSyncRegistryService } from 'vs/platform/userDataSync/common/storageKeys';
 import { StorageKeysSyncRegistryChannel } from 'vs/platform/userDataSync/common/userDataSyncIpc';
 import { INativeEnvironmentService } from 'vs/platform/environment/node/environmentService';
+import { mnemonicButtonLabel, getPathLabel } from 'vs/base/common/labels';
 
 export class CodeApplication extends Disposable {
 	private windowsMainService: IWindowsMainService | undefined;
@@ -605,6 +606,11 @@ export class CodeApplication extends Disposable {
 				return undefined;
 			}
 		})).filter(pendingUriToHandle => {
+			// if URI should be blocked, filter it out
+			if (this.shouldBlockURI(pendingUriToHandle)) {
+				return false;
+			}
+
 			// filter out any protocol link that wants to open as window so that
 			// we open the right set of windows on startup and not restore the
 			// previous workspace too.
@@ -623,6 +629,10 @@ export class CodeApplication extends Disposable {
 		const environmentService = this.environmentService;
 		urlService.registerHandler({
 			async handleURL(uri: URI): Promise<boolean> {
+				// if URI should be blocked, behave as if it's handled
+				if (app.shouldBlockURI(uri)) {
+					return true;
+				}
 
 				// Check for URIs to open in window
 				const windowOpenableFromProtocolLink = app.getWindowOpenableFromProtocolLink(uri);
@@ -727,6 +737,29 @@ export class CodeApplication extends Disposable {
 		});
 	}
 
+	private shouldBlockURI(uri: URI): boolean {
+		if (uri.authority === Schemas.file && isWindows) {
+			const res = dialog.showMessageBoxSync({
+				title: product.nameLong,
+				type: 'question',
+				buttons: [
+					mnemonicButtonLabel(localize({ key: 'open', comment: ['&& denotes a mnemonic'] }, "&&Yes")),
+					mnemonicButtonLabel(localize({ key: 'cancel', comment: ['&& denotes a mnemonic'] }, "&&No")),
+				],
+				cancelId: 1,
+				message: localize('confirmOpenMessage', "An external application wants to open '{0}' in {1}. Do you want to open this file or folder?", getPathLabel(uri.fsPath), product.nameShort),
+				detail: localize('confirmOpenDetail', "If you did not initiate this request, it may represent an attempted attack on your system. Unless you took an explicit action to initiate this request, you should press 'No'"),
+				noLink: true
+			});
+
+			if (res === 1) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 	private getWindowOpenableFromProtocolLink(uri: URI): IWindowOpenable | undefined {
 		if (!uri.path) {
 			return undefined;