diff --git a/Packet++/src/GreLayer.cpp b/Packet++/src/GreLayer.cpp
index da8b5d717..ff1000cc2 100644
--- a/Packet++/src/GreLayer.cpp
+++ b/Packet++/src/GreLayer.cpp
@@ -590,6 +590,11 @@ namespace pcpp
 
 	void PPP_PPTPLayer::computeCalculateFields()
 	{
+		if (m_DataLen < sizeof(ppp_pptp_header))
+		{
+			PCPP_LOG_ERROR("Insufficient data length for PPP_PPTP header");
+			return;
+		}
 		ppp_pptp_header* header = getPPP_PPTPHeader();
 		if (m_NextLayer != nullptr)
 		{