diff --git a/extensions/dashboard.ts b/extensions/dashboard.ts
index 1df2ee7..d89f181 100644
--- a/extensions/dashboard.ts
+++ b/extensions/dashboard.ts
@@ -593,6 +593,10 @@ export default function (pi: ExtensionAPI) {
         ctx.ui.notify(`Session already named "${name}"`, "info");
         return;
       }
+      if (/[/\\]/.test(name)) {
+        ctx.ui.notify(`Invalid name: "${name}" (no path separators allowed)`, "info");
+        return;
+      }
 
       const oldName = sessionName;
       sessionName = name;