diff --git a/code/datums/components/shell.dm b/code/datums/components/shell.dm
index ebe99cd4c2e..0e330a3547b 100644
--- a/code/datums/components/shell.dm
+++ b/code/datums/components/shell.dm
@@ -355,6 +355,10 @@
 		source.balloon_alert(user, "no circuit inside")
 		return COMSIG_CANCEL_USB_CABLE_ATTACK
 
+	if(attached_circuit.locked)
+		source.balloon_alert(user, "circuit is locked!")
+		return COMSIG_CANCEL_USB_CABLE_ATTACK
+	
 	usb_cable.attached_circuit = attached_circuit
 	return COMSIG_USB_CABLE_CONNECTED_TO_CIRCUIT
 
diff --git a/code/datums/components/usb_port.dm b/code/datums/components/usb_port.dm
index e4022f5ff18..f4e24224268 100644
--- a/code/datums/components/usb_port.dm
+++ b/code/datums/components/usb_port.dm
@@ -153,6 +153,10 @@
 			connecting_cable.balloon_alert(user, "too far away")
 		return COMSIG_CANCEL_USB_CABLE_ATTACK
 
+	if (connecting_cable.attached_circuit.locked)
+		connecting_cable.balloon_alert(user, "shell is locked!")
+		return COMSIG_CANCEL_USB_CABLE_ATTACK
+	
 	usb_cable_ref = WEAKREF(connecting_cable)
 	attached_circuit = connecting_cable.attached_circuit