diff --git a/packages/desktop/src/main/ipc-origin.ts b/packages/desktop/src/main/ipc-origin.ts
new file mode 100644
index 0000000000..a5073f8f77
--- /dev/null
+++ b/packages/desktop/src/main/ipc-origin.ts
@@ -0,0 +1,7 @@
+export function isTrustedIpcUrl(value: string, devUrl = process.env.ELECTRON_RENDERER_URL) {
+  if (!URL.canParse(value)) return false
+  const url = new URL(value)
+  if (url.protocol === "oc:" && url.host === "renderer") return true
+  if (!devUrl || !URL.canParse(devUrl)) return false
+  return url.origin === new URL(devUrl).origin
+}
diff --git a/packages/desktop/src/main/ipc-policy.test.ts b/packages/desktop/src/main/ipc-policy.test.ts
new file mode 100644
index 0000000000..666ad47928
--- /dev/null
+++ b/packages/desktop/src/main/ipc-policy.test.ts
@@ -0,0 +1,20 @@
+import { describe, expect, test } from "bun:test"
+import { isTrustedIpcUrl } from "./ipc-origin"
+
+describe("isTrustedIpcUrl", () => {
+  test("allows packaged renderer pages", () => {
+    expect(isTrustedIpcUrl("oc://renderer/index.html", undefined)).toBe(true)
+  })
+
+  test("rejects other packaged and remote origins", () => {
+    expect(isTrustedIpcUrl("oc://attacker/index.html", undefined)).toBe(false)
+    expect(isTrustedIpcUrl("https://example.com", undefined)).toBe(false)
+    expect(isTrustedIpcUrl("not a url", undefined)).toBe(false)
+  })
+
+  test("allows only the configured development origin", () => {
+    const devUrl = "http://localhost:5173"
+    expect(isTrustedIpcUrl("http://localhost:5173/index.html", devUrl)).toBe(true)
+    expect(isTrustedIpcUrl("http://localhost:5174/index.html", devUrl)).toBe(false)
+  })
+})
diff --git a/packages/desktop/src/main/ipc-policy.ts b/packages/desktop/src/main/ipc-policy.ts
new file mode 100644
index 0000000000..4d090571e0
--- /dev/null
+++ b/packages/desktop/src/main/ipc-policy.ts
@@ -0,0 +1,31 @@
+import { ipcMain } from "electron"
+import type { IpcMainEvent, IpcMainInvokeEvent } from "electron"
+import { isTrustedIpcUrl } from "./ipc-origin"
+
+type IpcEvent = IpcMainEvent | IpcMainInvokeEvent
+
+export function handle<Args extends unknown[], Result>(
+  channel: string,
+  listener: (event: IpcMainInvokeEvent, ...args: Args) => Result,
+) {
+  ipcMain.handle(channel, (event, ...args) => {
+    requireTrustedIpcSender(event)
+    return listener(event, ...(args as Args))
+  })
+}
+
+export function on<Args extends unknown[]>(
+  channel: string,
+  listener: (event: IpcMainEvent, ...args: Args) => void,
+) {
+  ipcMain.on(channel, (event, ...args) => {
+    requireTrustedIpcSender(event)
+    listener(event, ...(args as Args))
+  })
+}
+
+function requireTrustedIpcSender(event: IpcEvent) {
+  const frame = event.senderFrame
+  if (frame === event.sender.mainFrame && isTrustedIpcUrl(frame.url)) return
+  throw new Error("Rejected IPC from untrusted renderer")
+}
diff --git a/packages/desktop/src/main/ipc.ts b/packages/desktop/src/main/ipc.ts
index 4563b688ac..925452e293 100644
--- a/packages/desktop/src/main/ipc.ts
+++ b/packages/desktop/src/main/ipc.ts
@@ -1,13 +1,14 @@
 import { execFile } from "node:child_process"
 import { stat } from "node:fs/promises"
 import { basename } from "node:path"
-import { app, BrowserWindow, Notification, clipboard, dialog, ipcMain, shell } from "electron"
+import { app, BrowserWindow, Notification, clipboard, dialog, shell } from "electron"
 import type { IpcMainEvent, IpcMainInvokeEvent } from "electron"
 import type { DesktopMenuAction } from "@opencode-ai/app/desktop-menu"
 
 import type { FatalRendererError, ServerReadyData, TitlebarTheme } from "../preload/types"
 import { runDesktopMenuAction } from "./desktop-menu-actions"
 import { setForceFocus } from "./debug"
+import { handle, on } from "./ipc-policy"
 import { assertAttachmentBudget, createPickedFileAuthorizations } from "./attachment-picker"
 import { getStore, removeStoreFileIfEmpty } from "./store"
 import { getPinchZoomEnabled, getWindowID, setPinchZoomEnabled, setTitlebar, updateTitlebar } from "./windows"
@@ -47,26 +48,26 @@ export function registerIpcHandlers(deps: Deps) {
   const updaterSubscriptions = createUpdaterSubscriptions()
   app.once("will-quit", updaterSubscriptions.clear)
 
-  ipcMain.handle("kill-sidecar", () => deps.killSidecar())
-  ipcMain.handle("await-initialization", () => deps.awaitInitialization())
-  ipcMain.handle("consume-initial-deep-links", () => deps.consumeInitialDeepLinks())
-  ipcMain.handle("get-default-server-url", () => deps.getDefaultServerUrl())
-  ipcMain.handle("set-default-server-url", (_event: IpcMainInvokeEvent, url: string | null) =>
+  handle("kill-sidecar", () => deps.killSidecar())
+  handle("await-initialization", () => deps.awaitInitialization())
+  handle("consume-initial-deep-links", () => deps.consumeInitialDeepLinks())
+  handle("get-default-server-url", () => deps.getDefaultServerUrl())
+  handle("set-default-server-url", (_event: IpcMainInvokeEvent, url: string | null) =>
     deps.setDefaultServerUrl(url),
   )
-  ipcMain.handle("is-first-launch-onboarding-pending", () => deps.isFirstLaunchOnboardingPending())
-  ipcMain.handle("finish-first-launch-onboarding", (_event: IpcMainInvokeEvent, createDefaultProject: boolean) =>
+  handle("is-first-launch-onboarding-pending", () => deps.isFirstLaunchOnboardingPending())
+  handle("finish-first-launch-onboarding", (_event: IpcMainInvokeEvent, createDefaultProject: boolean) =>
     deps.finishFirstLaunchOnboarding(createDefaultProject),
   )
-  ipcMain.handle("is-old-layout-eligible", () => deps.isOldLayoutEligible())
-  ipcMain.handle("get-display-backend", () => deps.getDisplayBackend())
-  ipcMain.handle("set-display-backend", (_event: IpcMainInvokeEvent, backend: string | null) =>
+  handle("is-old-layout-eligible", () => deps.isOldLayoutEligible())
+  handle("get-display-backend", () => deps.getDisplayBackend())
+  handle("set-display-backend", (_event: IpcMainInvokeEvent, backend: string | null) =>
     deps.setDisplayBackend(backend),
   )
-  ipcMain.handle("parse-markdown", (_event: IpcMainInvokeEvent, markdown: string) => deps.parseMarkdown(markdown))
-  ipcMain.handle("check-app-exists", (_event: IpcMainInvokeEvent, appName: string) => deps.checkAppExists(appName))
-  ipcMain.handle("resolve-app-path", (_event: IpcMainInvokeEvent, appName: string) => deps.resolveAppPath(appName))
-  ipcMain.handle("updater-subscribe", (event) => {
+  handle("parse-markdown", (_event: IpcMainInvokeEvent, markdown: string) => deps.parseMarkdown(markdown))
+  handle("check-app-exists", (_event: IpcMainInvokeEvent, appName: string) => deps.checkAppExists(appName))
+  handle("resolve-app-path", (_event: IpcMainInvokeEvent, appName: string) => deps.resolveAppPath(appName))
+  handle("updater-subscribe", (event) => {
     const id = event.sender.id
     updaterSubscriptions.set(
       id,
@@ -77,18 +78,18 @@ export function registerIpcHandlers(deps: Deps) {
     )
     event.sender.once("destroyed", () => updaterSubscriptions.delete(id))
   })
-  ipcMain.handle("updater-unsubscribe", (event) => updaterSubscriptions.delete(event.sender.id))
-  ipcMain.handle("updater-check", () => deps.updater.check())
-  ipcMain.handle("updater-install", () => deps.updater.install())
-  ipcMain.handle("set-background-color", (_event: IpcMainInvokeEvent, color: string) => deps.setBackgroundColor(color))
-  ipcMain.handle("export-debug-logs", () => deps.exportDebugLogs())
-  ipcMain.handle("set-force-focus", (event: IpcMainInvokeEvent, enabled: boolean) =>
+  handle("updater-unsubscribe", (event) => updaterSubscriptions.delete(event.sender.id))
+  handle("updater-check", () => deps.updater.check())
+  handle("updater-install", () => deps.updater.install())
+  handle("set-background-color", (_event: IpcMainInvokeEvent, color: string) => deps.setBackgroundColor(color))
+  handle("export-debug-logs", () => deps.exportDebugLogs())
+  handle("set-force-focus", (event: IpcMainInvokeEvent, enabled: boolean) =>
     setForceFocus(event.sender, enabled),
   )
-  ipcMain.handle("record-fatal-renderer-error", (_event: IpcMainInvokeEvent, error: FatalRendererError) =>
+  handle("record-fatal-renderer-error", (_event: IpcMainInvokeEvent, error: FatalRendererError) =>
     deps.recordFatalRendererError(error),
   )
-  ipcMain.handle("store-get", (_event: IpcMainInvokeEvent, name: string, key: string) => {
+  handle("store-get", (_event: IpcMainInvokeEvent, name: string, key: string) => {
     try {
       const store = getStore(name)
       const value = store.get(key)
@@ -98,27 +99,27 @@ export function registerIpcHandlers(deps: Deps) {
       return null
     }
   })
-  ipcMain.handle("store-set", (_event: IpcMainInvokeEvent, name: string, key: string, value: string) => {
+  handle("store-set", (_event: IpcMainInvokeEvent, name: string, key: string, value: string) => {
     getStore(name).set(key, value)
   })
-  ipcMain.handle("store-delete", (_event: IpcMainInvokeEvent, name: string, key: string) => {
+  handle("store-delete", (_event: IpcMainInvokeEvent, name: string, key: string) => {
     getStore(name).delete(key)
     void removeStoreFileIfEmpty(name)
   })
-  ipcMain.handle("store-clear", (_event: IpcMainInvokeEvent, name: string) => {
+  handle("store-clear", (_event: IpcMainInvokeEvent, name: string) => {
     getStore(name).clear()
     void removeStoreFileIfEmpty(name)
   })
-  ipcMain.handle("store-keys", (_event: IpcMainInvokeEvent, name: string) => {
+  handle("store-keys", (_event: IpcMainInvokeEvent, name: string) => {
     const store = getStore(name)
     return Object.keys(store.store)
   })
-  ipcMain.handle("store-length", (_event: IpcMainInvokeEvent, name: string) => {
+  handle("store-length", (_event: IpcMainInvokeEvent, name: string) => {
     const store = getStore(name)
     return Object.keys(store.store).length
   })
 
-  ipcMain.handle(
+  handle(
     "open-directory-picker",
     async (_event: IpcMainInvokeEvent, opts?: { multiple?: boolean; title?: string; defaultPath?: string }) => {
       const result = await dialog.showOpenDialog({
@@ -131,7 +132,7 @@ export function registerIpcHandlers(deps: Deps) {
     },
   )
 
-  ipcMain.handle(
+  handle(
     "open-file-picker",
     async (
       event: IpcMainInvokeEvent,
@@ -157,15 +158,15 @@ export function registerIpcHandlers(deps: Deps) {
     },
   )
 
-  ipcMain.handle("read-picked-file", async (event: IpcMainInvokeEvent, token: string, filePath: string) => {
+  handle("read-picked-file", async (event: IpcMainInvokeEvent, token: string, filePath: string) => {
     return pickedFiles.read(event.sender.id, token, filePath)
   })
 
-  ipcMain.handle("release-picked-files", (event: IpcMainInvokeEvent, token: string) => {
+  handle("release-picked-files", (event: IpcMainInvokeEvent, token: string) => {
     pickedFiles.release(event.sender.id, token)
   })
 
-  ipcMain.handle(
+  handle(
     "save-file-picker",
     async (_event: IpcMainInvokeEvent, opts?: { title?: string; defaultPath?: string }) => {
       const result = await dialog.showSaveDialog({
@@ -177,11 +178,11 @@ export function registerIpcHandlers(deps: Deps) {
     },
   )
 
-  ipcMain.on("open-link", (_event: IpcMainEvent, url: string) => {
+  on("open-link", (_event: IpcMainEvent, url: string) => {
     void shell.openExternal(url)
   })
 
-  ipcMain.handle("open-path", async (_event: IpcMainInvokeEvent, path: string, app?: string) => {
+  handle("open-path", async (_event: IpcMainInvokeEvent, path: string, app?: string) => {
     if (!app) return shell.openPath(path)
     await new Promise<void>((resolve, reject) => {
       const [cmd, args] =
@@ -190,7 +191,7 @@ export function registerIpcHandlers(deps: Deps) {
     })
   })
 
-  ipcMain.handle("reveal-path", async (_event: IpcMainInvokeEvent, path: string) => {
+  handle("reveal-path", async (_event: IpcMainInvokeEvent, path: string) => {
     const exists = await stat(path).then(
       () => true,
       () => false,
@@ -200,7 +201,7 @@ export function registerIpcHandlers(deps: Deps) {
     return true
   })
 
-  ipcMain.handle("read-clipboard-image", () => {
+  handle("read-clipboard-image", () => {
     const image = clipboard.readImage()
     if (image.isEmpty()) return null
     const buffer = image.toPNG().buffer
@@ -208,13 +209,13 @@ export function registerIpcHandlers(deps: Deps) {
     return { buffer, width: size.width, height: size.height }
   })
 
-  ipcMain.on("show-notification", (_event: IpcMainEvent, title: string, body?: string) => {
+  on("show-notification", (_event: IpcMainEvent, title: string, body?: string) => {
     new Notification({ title, body }).show()
   })
 
-  ipcMain.handle("get-window-count", () => BrowserWindow.getAllWindows().length)
+  handle("get-window-count", () => BrowserWindow.getAllWindows().length)
 
-  ipcMain.handle("get-window-id", (event: IpcMainInvokeEvent) => {
+  handle("get-window-id", (event: IpcMainInvokeEvent) => {
     const win = BrowserWindow.fromWebContents(event.sender)
     if (!win) throw new Error("Window not found")
     const id = getWindowID(win)
@@ -222,42 +223,42 @@ export function registerIpcHandlers(deps: Deps) {
     return id
   })
 
-  ipcMain.handle("get-window-focused", (event: IpcMainInvokeEvent) => {
+  handle("get-window-focused", (event: IpcMainInvokeEvent) => {
     const win = BrowserWindow.fromWebContents(event.sender)
     return win?.isFocused() ?? false
   })
 
-  ipcMain.handle("set-window-focus", (event: IpcMainInvokeEvent) => {
+  handle("set-window-focus", (event: IpcMainInvokeEvent) => {
     const win = BrowserWindow.fromWebContents(event.sender)
     win?.focus()
   })
 
-  ipcMain.handle("show-window", (event: IpcMainInvokeEvent) => {
+  handle("show-window", (event: IpcMainInvokeEvent) => {
     const win = BrowserWindow.fromWebContents(event.sender)
     win?.show()
   })
 
-  ipcMain.on("relaunch", () => {
+  on("relaunch", () => {
     deps.relaunch()
   })
 
-  ipcMain.handle("get-zoom-factor", (event: IpcMainInvokeEvent) => event.sender.getZoomFactor())
-  ipcMain.handle("set-zoom-factor", (event: IpcMainInvokeEvent, factor: number) => {
+  handle("get-zoom-factor", (event: IpcMainInvokeEvent) => event.sender.getZoomFactor())
+  handle("set-zoom-factor", (event: IpcMainInvokeEvent, factor: number) => {
     event.sender.setZoomFactor(factor)
     const win = BrowserWindow.fromWebContents(event.sender)
     if (!win) return
     updateTitlebar(win)
   })
-  ipcMain.handle("get-pinch-zoom-enabled", () => getPinchZoomEnabled())
-  ipcMain.handle("set-pinch-zoom-enabled", (_event: IpcMainInvokeEvent, enabled: boolean) => {
+  handle("get-pinch-zoom-enabled", () => getPinchZoomEnabled())
+  handle("set-pinch-zoom-enabled", (_event: IpcMainInvokeEvent, enabled: boolean) => {
     setPinchZoomEnabled(enabled)
   })
-  ipcMain.handle("set-titlebar", (event: IpcMainInvokeEvent, theme: TitlebarTheme) => {
+  handle("set-titlebar", (event: IpcMainInvokeEvent, theme: TitlebarTheme) => {
     const win = BrowserWindow.fromWebContents(event.sender)
     if (!win) return
     setTitlebar(win, theme)
   })
-  ipcMain.handle("run-desktop-menu-action", (event: IpcMainInvokeEvent, action: DesktopMenuAction) => {
+  handle("run-desktop-menu-action", (event: IpcMainInvokeEvent, action: DesktopMenuAction) => {
     runDesktopMenuAction(BrowserWindow.fromWebContents(event.sender), action, {
       checkForUpdates: () => void deps.showUpdater(),
       relaunch: deps.relaunch,
diff --git a/packages/desktop/src/main/wsl/ipc.ts b/packages/desktop/src/main/wsl/ipc.ts
index c3a2271bf6..ed2872f5bf 100644
--- a/packages/desktop/src/main/wsl/ipc.ts
+++ b/packages/desktop/src/main/wsl/ipc.ts
@@ -1,8 +1,9 @@
-import { app, ipcMain } from "electron"
+import { app } from "electron"
 import type { IpcMainInvokeEvent } from "electron"
 import type { WslServersController } from "./servers"
 import { requireWslIpcString, requireWslIpcStrings } from "./policy"
 import type { WslServersState } from "../../preload/types"
+import { handle } from "../ipc-policy"
 
 export function registerWslIpcHandlers(controller: WslServersController) {
   if (process.platform !== "win32") {
@@ -23,7 +24,7 @@ export function registerWslIpcHandlers(controller: WslServersController) {
     subscriptions.clear()
   })
 
-  ipcMain.handle("wsl-servers-subscribe", (event) => {
+  handle("wsl-servers-subscribe", (event) => {
     const id = event.sender.id
     if (subscriptions.has(id)) return
     subscriptions.set(
@@ -38,30 +39,30 @@ export function registerWslIpcHandlers(controller: WslServersController) {
     )
     event.sender.once("destroyed", () => unsubscribe(id))
   })
-  ipcMain.handle("wsl-servers-unsubscribe", (event) => unsubscribe(event.sender.id))
-  ipcMain.handle("wsl-servers-get-state", () => controller.getState())
-  ipcMain.handle("wsl-servers-probe-runtime", () => controller.probeRuntime())
-  ipcMain.handle("wsl-servers-refresh-distros", () => controller.refreshDistros())
-  ipcMain.handle("wsl-servers-install-wsl", () => controller.installWsl())
-  ipcMain.handle("wsl-servers-install-distro", (_event: IpcMainInvokeEvent, name: string) =>
+  handle("wsl-servers-unsubscribe", (event) => unsubscribe(event.sender.id))
+  handle("wsl-servers-get-state", () => controller.getState())
+  handle("wsl-servers-probe-runtime", () => controller.probeRuntime())
+  handle("wsl-servers-refresh-distros", () => controller.refreshDistros())
+  handle("wsl-servers-install-wsl", () => controller.installWsl())
+  handle("wsl-servers-install-distro", (_event: IpcMainInvokeEvent, name: string) =>
     controller.installDistro(requireWslIpcString("distro", name)),
   )
-  ipcMain.handle("wsl-servers-probe-addable", (_event: IpcMainInvokeEvent, distros: string[]) =>
+  handle("wsl-servers-probe-addable", (_event: IpcMainInvokeEvent, distros: string[]) =>
     controller.probeAddable(requireWslIpcStrings("distro", distros)),
   )
-  ipcMain.handle("wsl-servers-install-opencode", (_event: IpcMainInvokeEvent, name: string) =>
+  handle("wsl-servers-install-opencode", (_event: IpcMainInvokeEvent, name: string) =>
     controller.installOpencode(requireWslIpcString("distro", name)),
   )
-  ipcMain.handle("wsl-servers-open-terminal", (_event: IpcMainInvokeEvent, name: string) =>
+  handle("wsl-servers-open-terminal", (_event: IpcMainInvokeEvent, name: string) =>
     controller.openTerminal(requireWslIpcString("distro", name)),
   )
-  ipcMain.handle("wsl-servers-add", (_event: IpcMainInvokeEvent, distro: string) =>
+  handle("wsl-servers-add", (_event: IpcMainInvokeEvent, distro: string) =>
     controller.addServer(requireWslIpcString("distro", distro)),
   )
-  ipcMain.handle("wsl-servers-remove", (_event: IpcMainInvokeEvent, id: string) =>
+  handle("wsl-servers-remove", (_event: IpcMainInvokeEvent, id: string) =>
     controller.removeServer(requireWslIpcString("server id", id)),
   )
-  ipcMain.handle("wsl-servers-start", (_event: IpcMainInvokeEvent, id: string) =>
+  handle("wsl-servers-start", (_event: IpcMainInvokeEvent, id: string) =>
     controller.startServer(requireWslIpcString("server id", id)),
   )
 }
@@ -85,19 +86,19 @@ function registerUnavailableWslIpcHandlers() {
     job: null,
   })
 
-  ipcMain.handle("wsl-servers-subscribe", (event) => {
+  handle("wsl-servers-subscribe", (event) => {
     event.sender.send("wsl-servers-event", { type: "state", state: state() })
   })
-  ipcMain.handle("wsl-servers-unsubscribe", () => undefined)
-  ipcMain.handle("wsl-servers-get-state", () => state())
-  ipcMain.handle("wsl-servers-probe-runtime", unavailable)
-  ipcMain.handle("wsl-servers-refresh-distros", unavailable)
-  ipcMain.handle("wsl-servers-install-wsl", unavailable)
-  ipcMain.handle("wsl-servers-install-distro", unavailable)
-  ipcMain.handle("wsl-servers-probe-addable", unavailable)
-  ipcMain.handle("wsl-servers-install-opencode", unavailable)
-  ipcMain.handle("wsl-servers-open-terminal", unavailable)
-  ipcMain.handle("wsl-servers-add", unavailable)
-  ipcMain.handle("wsl-servers-remove", unavailable)
-  ipcMain.handle("wsl-servers-start", unavailable)
+  handle("wsl-servers-unsubscribe", () => undefined)
+  handle("wsl-servers-get-state", () => state())
+  handle("wsl-servers-probe-runtime", unavailable)
+  handle("wsl-servers-refresh-distros", unavailable)
+  handle("wsl-servers-install-wsl", unavailable)
+  handle("wsl-servers-install-distro", unavailable)
+  handle("wsl-servers-probe-addable", unavailable)
+  handle("wsl-servers-install-opencode", unavailable)
+  handle("wsl-servers-open-terminal", unavailable)
+  handle("wsl-servers-add", unavailable)
+  handle("wsl-servers-remove", unavailable)
+  handle("wsl-servers-start", unavailable)
 }