diff --git a/vendor/manifest b/vendor/manifest
index 3be82729..29e98612 100644
--- a/vendor/manifest
+++ b/vendor/manifest
@@ -74,7 +74,7 @@
 		{
 			"importpath": "github.com/matrix-org/util",
 			"repository": "https://github.com/matrix-org/util",
-			"revision": "2aeb7e5d047ec74d65353f1579990a1e90af5bb0",
+			"revision": "0f4d9cce82badc0741ff1141dcf079312cb4d2f0",
 			"branch": "master"
 		},
 		{
diff --git a/vendor/src/github.com/matrix-org/util/json.go b/vendor/src/github.com/matrix-org/util/json.go
index 4277a063..ac29a138 100644
--- a/vendor/src/github.com/matrix-org/util/json.go
+++ b/vendor/src/github.com/matrix-org/util/json.go
@@ -7,6 +7,7 @@ import (
 	"math/rand"
 	"net/http"
 	"runtime/debug"
+	"time"
 
 	log "github.com/Sirupsen/logrus"
 )
@@ -152,3 +153,7 @@ func RandomString(n int) string {
 	}
 	return string(b)
 }
+
+func init() {
+	rand.Seed(time.Now().UTC().UnixNano())
+}