diff --git a/src/libcharon/plugins/eap_ttls/eap_ttls_peer.c b/src/libcharon/plugins/eap_ttls/eap_ttls_peer.c
index 66c9deed8..e0b59a681 100644
--- a/src/libcharon/plugins/eap_ttls/eap_ttls_peer.c
+++ b/src/libcharon/plugins/eap_ttls/eap_ttls_peer.c
@@ -112,6 +112,13 @@ METHOD(tls_application_t, process, status_t,
 				eap_data = avp_data;
 				break;
 			}
+			else if (eap_len > reader->remaining(reader) + avp_data.len)
+			{
+				/* rough size check, ignoring AVP headers in remaining data */
+				DBG1(DBG_IKE, "EAP packet too large for EAP-TTLS AVP(s)");
+				chunk_free(&avp_data);
+				return FAILED;
+			}
 			else if (avp_data.len == MAX_RADIUS_ATTRIBUTE_SIZE)
 			{
 				/* non-standard: EAP packet segmented into multiple AVPs */
@@ -128,7 +135,7 @@ METHOD(tls_application_t, process, status_t,
 
 		if (avp_data.len > eap_data.len - eap_pos)
 		{
-			DBG1(DBG_IKE, "AVP size to large to fit into EAP packet");
+			DBG1(DBG_IKE, "AVP size too large to fit into EAP packet");
 			chunk_free(&avp_data);
 			chunk_free(&eap_data);
 			return FAILED;