diff --git a/src/utils/json.c b/src/utils/json.c
index b9130d3a6..c6ada0548 100644
--- a/src/utils/json.c
+++ b/src/utils/json.c
@@ -165,6 +165,8 @@ static int json_parse_number(const char **json_pos, const char *end,
 			break;
 		}
 	}
+	if (pos == end)
+		pos--;
 	if (pos < *json_pos)
 		return -1;
 	len = pos - *json_pos + 1;