diff --git a/src/core/coap/coap_message.cpp b/src/core/coap/coap_message.cpp
index 5580e0a08..627302535 100644
--- a/src/core/coap/coap_message.cpp
+++ b/src/core/coap/coap_message.cpp
@@ -268,7 +268,7 @@ const otCoapOption *Message::GetNextOption(void)
     }
     else
     {
-        ExitNow();
+        ExitNow(error = OT_ERROR_PARSE);
     }
 
     VerifyOrExit(optionLength <= GetLength() - GetHelpData().mNextOptionOffset, error = OT_ERROR_PARSE);