diff --git a/crypto/asn1/a_time.c b/crypto/asn1/a_time.c
index 6e5e9d845d..3a03c9e4e4 100644
--- a/crypto/asn1/a_time.c
+++ b/crypto/asn1/a_time.c
@@ -152,7 +152,7 @@ ASN1_GENERALIZEDTIME *ASN1_TIME_to_generalizedtime(ASN1_TIME *t, ASN1_GENERALIZE
 	if (t->data[0] >= '5') strcpy(str, "19");
 	else strcpy(str, "20");
 
-	BUF_strlcat(str, (char *)t->data, t->length+2);
+	BUF_strlcat(str, (char *)t->data, t->length+3);	/* Include space for a '\0' */
 
 	return ret;
 	}