diff --git a/adapters/vim/bridge.ts b/adapters/vim/bridge.ts
index 80f8ce6..cdee6c9 100644
--- a/adapters/vim/bridge.ts
+++ b/adapters/vim/bridge.ts
@@ -42,10 +42,16 @@ function connect(roomName: string) {
       case "sync":
       case "update": {
         if (!doc) break;
-        suppressLocal = true;
-        Y.applyUpdate(doc, new Uint8Array(msg.data));
-        suppressLocal = false;
-        send({ type: "content", text: text?.toString() || "" });
+        try {
+          suppressLocal = true;
+          Y.applyUpdate(doc, new Uint8Array(msg.data));
+          suppressLocal = false;
+          send({ type: "content", text: text?.toString() || "" });
+        } catch (err) {
+          suppressLocal = false;
+          console.error("failed to apply yjs update:", err);
+          send({ type: "error", message: "failed to apply remote update" });
+        }
         break;
       }
       case "peers": {
diff --git a/src/session.ts b/src/session.ts
index 01763c8..dbde65b 100644
--- a/src/session.ts
+++ b/src/session.ts
@@ -28,11 +28,21 @@ export class Session {
   }
 
   applyUpdate(update: Uint8Array, from: Client) {
-    Y.applyUpdate(this.doc, update);
-    // broadcast to others
-    for (const client of this.clients) {
-      if (client !== from) {
-        client.ws.send(encode({ type: "update", data: Array.from(update) }));
+    try {
+      Y.applyUpdate(this.doc, update);
+      // broadcast to others
+      for (const client of this.clients) {
+        if (client !== from) {
+          client.ws.send(encode({ type: "update", data: Array.from(update) }));
+        }
+      }
+    } catch (err) {
+      console.error(`failed to apply update in session ${this.name}:`, err);
+      // optionally notify the client that sent the bad update
+      try {
+        from.ws.send(encode({ type: "error", message: "invalid update" } as any));
+      } catch {
+        // ignore send errors
       }
     }
   }