diff --git a/apps/cistech-tunnel/build/Dockerfile b/apps/cistech-tunnel/build/Dockerfile
index 3e9e837..fb9d96e 100644
--- a/apps/cistech-tunnel/build/Dockerfile
+++ b/apps/cistech-tunnel/build/Dockerfile
@@ -34,10 +34,9 @@ RUN apt-get update && apt-get install -y \
     python3 \
     python3-pip \
     python3-venv \
-    # VNC/noVNC
+    # VNC/noVNC (novnc installed from GitHub below)
     tigervnc-standalone-server \
     tigervnc-common \
-    novnc \
     websockify \
     x11vnc \
     xvfb \
@@ -93,6 +92,11 @@ RUN apt-get update && apt-get install -y \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
+# Install noVNC from GitHub (v1.4.0 - stable release with ES6 modules)
+RUN curl -fsSL https://github.com/novnc/noVNC/archive/refs/tags/v1.4.0.tar.gz | tar -xz -C /usr/share/ \
+    && mv /usr/share/noVNC-1.4.0 /usr/share/novnc \
+    && ln -sf /usr/share/novnc/vnc.html /usr/share/novnc/index.html
+
 # Create Python venv and install openconnect-sso with all dependencies
 RUN python3 -m venv "$VIRTUAL_ENV" && \
     pip install --no-cache-dir --upgrade pip && \