diff --git a/src/libCom/cvtFast.c b/src/libCom/cvtFast.c
index 9312031b3..bc250042b 100644
--- a/src/libCom/cvtFast.c
+++ b/src/libCom/cvtFast.c
@@ -151,6 +151,7 @@ int cvtDoubleToString(
 	/* can this routine handle this conversion */
 	if (precision > 8 || flt_value > 10000000.0 || flt_value < -10000000.0) {
 		if (precision > 8 || flt_value > 1e16 || flt_value < -1e16) {
+		    if(precision>17) precision=17;
 		    sprintf(pstr_value,"%*.*e\0",precision+7,precision,
 			flt_value);
 		} else {
diff --git a/src/libCom/cvtFast/cvtFast.c b/src/libCom/cvtFast/cvtFast.c
index 9312031b3..bc250042b 100644
--- a/src/libCom/cvtFast/cvtFast.c
+++ b/src/libCom/cvtFast/cvtFast.c
@@ -151,6 +151,7 @@ int cvtDoubleToString(
 	/* can this routine handle this conversion */
 	if (precision > 8 || flt_value > 10000000.0 || flt_value < -10000000.0) {
 		if (precision > 8 || flt_value > 1e16 || flt_value < -1e16) {
+		    if(precision>17) precision=17;
 		    sprintf(pstr_value,"%*.*e\0",precision+7,precision,
 			flt_value);
 		} else {