diff --git a/Overlord-Server/src/main-server.ts b/Overlord-Server/src/main-server.ts
index 5e10985..6cfbc56 100644
--- a/Overlord-Server/src/main-server.ts
+++ b/Overlord-Server/src/main-server.ts
@@ -537,7 +537,7 @@ async function startServer() {
     takePendingNotificationScreenshot: takePendingNotificationScreenshotForClient,
     storeNotificationScreenshot: storeNotificationScreenshotForPending,
     handleNotificationScreenshotResult: notificationPluginHandlers.handleNotificationScreenshotResult,
-    handleConsoleOutput,
+    handleConsoleOutput: (clientId: string, payload: any) => handleConsoleOutput(clientId, payload),
     handleFileBrowserMessage: (clientId: string, payload: any) =>
       forwardFileBrowserMessage(clientId, payload, {
         pendingHttpDownloads,
diff --git a/Overlord-Server/src/server/routes/websocket-lifecycle-routes.ts b/Overlord-Server/src/server/routes/websocket-lifecycle-routes.ts
index cb78c5c..8fd038a 100644
--- a/Overlord-Server/src/server/routes/websocket-lifecycle-routes.ts
+++ b/Overlord-Server/src/server/routes/websocket-lifecycle-routes.ts
@@ -65,7 +65,7 @@ type WsLifecycleDeps = {
     height?: number,
   ) => void;
   handleNotificationScreenshotResult: (clientId: string, payload: any) => void;
-  handleConsoleOutput: (payload: any) => void;
+  handleConsoleOutput: (clientId: string, payload: any) => void;
   handleFileBrowserMessage: (clientId: string, payload: any) => void;
   handleProxyTunnelData: (clientId: string, connectionId: string, data: Uint8Array) => void;
   handleProxyTunnelClose: (clientId: string, connectionId: string) => void;
@@ -290,20 +290,24 @@ export async function handleWebSocketMessage(
           const countryRaw = geo?.country || (payload as any).country || "ZZ";
           const country = /^[A-Z]{2}$/i.test(countryRaw) ? countryRaw.toUpperCase() : "ZZ";
 
+          const _s = (v: unknown, max = 256): string | undefined => {
+            if (typeof v !== "string") return undefined;
+            return v.replace(/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F]/g, "").slice(0, max);
+          };
           upsertClientRow({
             id: resolvedId,
-            hwid: (payload as any).hwid || resolvedId,
+            hwid: _s((payload as any).hwid) || resolvedId,
             role: "client",
             ip: ip || undefined,
-            host: (payload as any).host || undefined,
-            os: (payload as any).os || undefined,
-            arch: (payload as any).arch || undefined,
-            version: (payload as any).version || undefined,
-            user: (payload as any).user || undefined,
+            host: _s((payload as any).host),
+            os: _s((payload as any).os),
+            arch: _s((payload as any).arch, 32),
+            version: _s((payload as any).version, 64),
+            user: _s((payload as any).user),
             monitors: (payload as any).monitors || undefined,
-            cpu: (payload as any).cpu || undefined,
-            gpu: (payload as any).gpu || undefined,
-            ram: (payload as any).ram || undefined,
+            cpu: _s((payload as any).cpu),
+            gpu: _s((payload as any).gpu),
+            ram: _s((payload as any).ram, 64),
             country,
             lastSeen: Date.now(),
             online: 0 as any,
@@ -319,17 +323,17 @@ export async function handleWebSocketMessage(
           deps.notifyDashboard();
           deps.notifyDashboardClientEvent("client_purgatory", {
             id: resolvedId,
-            host: (payload as any).host || undefined,
-            user: (payload as any).user || undefined,
-            os: (payload as any).os || undefined,
+            host: _s((payload as any).host),
+            user: _s((payload as any).user),
+            os: _s((payload as any).os),
             ip: ip || undefined,
             country,
           });
           deps.broadcastClientEvent("client_purgatory", {
             id: resolvedId,
-            host: (payload as any).host || undefined,
-            user: (payload as any).user || undefined,
-            os: (payload as any).os || undefined,
+            host: _s((payload as any).host),
+            user: _s((payload as any).user),
+            os: _s((payload as any).os),
             ip: ip || undefined,
             country,
           });
@@ -468,7 +472,7 @@ export async function handleWebSocketMessage(
         deps.handleNotificationScreenshotResult(client.id, payload);
         break;
       case "console_output":
-        deps.handleConsoleOutput(payload);
+        deps.handleConsoleOutput(client.id, payload);
         break;
       case "file_list_result":
       case "file_download":
diff --git a/Overlord-Server/src/server/ws-console-rd-hvnc.ts b/Overlord-Server/src/server/ws-console-rd-hvnc.ts
index 1a6e462..82dbdea 100644
--- a/Overlord-Server/src/server/ws-console-rd-hvnc.ts
+++ b/Overlord-Server/src/server/ws-console-rd-hvnc.ts
@@ -911,11 +911,12 @@ export function handleConsoleViewerMessage(ws: ServerWebSocket<SocketData>, raw:
   }
 }
 
-export function handleConsoleOutput(payload: any) {
+export function handleConsoleOutput(clientId: string, payload: any) {
   const sessionId = payload.sessionId as string;
   if (!sessionId) return;
   const session = sessionManager.getConsoleSession(sessionId);
   if (!session) return;
+  if (session.clientId !== clientId) return;
   const data = payload.data ? textDecoder.decode(payload.data as Uint8Array) : "";
   safeSendViewer(session.viewer, {
     type: "output",
diff --git a/Overlord-Server/src/wsHandlers.ts b/Overlord-Server/src/wsHandlers.ts
index 8b183ca..928915a 100644
--- a/Overlord-Server/src/wsHandlers.ts
+++ b/Overlord-Server/src/wsHandlers.ts
@@ -11,6 +11,12 @@ import {
 import { upsertClientRow } from "./db";
 import { metrics } from "./metrics";
 
+/** Strip control chars and clamp length on client-supplied info strings. */
+function sanitizeInfoString(val: unknown, maxLen = 256): string | undefined {
+  if (typeof val !== "string") return undefined;
+  return val.replace(/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F]/g, "").slice(0, maxLen);
+}
+
 const MAX_PING_RTT_MS = 15_000;
 const CLIENT_DB_SYNC_INTERVAL_MS = Number(process.env.OVERLORD_CLIENT_DB_SYNC_MS || 5000);
 const lastClientDbSync = new Map<string, number>();
@@ -80,23 +86,23 @@ export function handleHello(
   if (ip) {
     info.ip = ip;
   }
-  info.hwid = (payload as any).hwid as string | undefined;
-  info.host = payload.host;
-  info.os = payload.os;
-  info.arch = payload.arch;
-  info.version = payload.version;
-  info.user = payload.user;
+  info.hwid = sanitizeInfoString((payload as any).hwid);
+  info.host = sanitizeInfoString(payload.host);
+  info.os = sanitizeInfoString(payload.os);
+  info.arch = sanitizeInfoString(payload.arch, 32);
+  info.version = sanitizeInfoString(payload.version, 64);
+  info.user = sanitizeInfoString(payload.user);
   info.monitors = payload.monitors;
   info.monitorInfo = (payload as any).monitorInfo || info.monitorInfo;
   info.inMemory = !!(payload as any).inMemory;
   info.isAdmin = !!(payload as any).isAdmin;
-  info.elevation = typeof (payload as any).elevation === "string" ? (payload as any).elevation : info.elevation;
+  info.elevation = sanitizeInfoString((payload as any).elevation, 32) ?? info.elevation;
   if ((payload as any).permissions && typeof (payload as any).permissions === "object") {
     info.permissions = (payload as any).permissions;
   }
-  info.cpu = (payload as any).cpu || info.cpu;
-  info.gpu = (payload as any).gpu || info.gpu;
-  info.ram = (payload as any).ram || info.ram;
+  info.cpu = sanitizeInfoString((payload as any).cpu) || info.cpu;
+  info.gpu = sanitizeInfoString((payload as any).gpu) || info.gpu;
+  info.ram = sanitizeInfoString((payload as any).ram, 64) || info.ram;
   const geo = ip ? geoip.lookup(ip) : undefined;
   const countryRaw =
     geo?.country || (payload as any).country || info.country || "ZZ";