diff --git a/src/util/virauth.c b/src/util/virauth.c
index 8c450b6b31..759b8f0cd3 100644
--- a/src/util/virauth.c
+++ b/src/util/virauth.c
@@ -198,6 +198,12 @@ virAuthGetUsername(virConnectPtr conn,
     if (virAuthGetConfigFilePath(conn, &path) < 0)
         return NULL;
 
+    if (!auth || !auth->cb) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("Missing or invalid auth pointer"));
+        return NULL;
+    }
+
     return virAuthGetUsernamePath(path, auth, servicename,
                                  defaultUsername, hostname);
 }
@@ -262,5 +268,11 @@ virAuthGetPassword(virConnectPtr conn,
     if (virAuthGetConfigFilePath(conn, &path) < 0)
         return NULL;
 
+    if (!auth || !auth->cb) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("Missing or invalid auth pointer"));
+        return NULL;
+    }
+
     return virAuthGetPasswordPath(path, auth, servicename, username, hostname);
 }