diff --git a/src/at.c b/src/at.c
index ee99ff4..56dbe76 100644
--- a/src/at.c
+++ b/src/at.c
@@ -245,7 +245,14 @@ static gboolean modem_response(gint fd,
      */
     do {
         ret = read(fd, tmp, sizeof(tmp));
+
         if (ret > 0) {
+            /* If we're going to overflow truncate the data we read to fit */
+            if (pos + ret >= sizeof(response)) {
+                g_critical("AT response buffer full, truncating");
+                ret = sizeof(response) - (pos + 1);
+            }
+
             memcpy(&response[pos], tmp, ret);
             pos += ret;
             usleep(10000);