diff --git a/integration/Dockerfile b/integration/Dockerfile
index 8d9af61b31..e735092cd4 100644
--- a/integration/Dockerfile
+++ b/integration/Dockerfile
@@ -1,6 +1,6 @@
 # This Dockerfile builds a base image for the certificate-transparency-go CloudBuild integration testing.
 # See https://hub.docker.com/_/golang for the set of golang base images.
-FROM golang:1.21.4-bookworm@sha256:52362e252f452df17c24131b021bf2ebf1c9869f65c28f88ddb326191defea9c as ct_testbase
+FROM golang:1.21.5-bookworm@sha256:a6b787c7f9046e3fdaa97bca1f76fd23ff4108f612de885e1af87e0dccc02f99 as ct_testbase
 
 WORKDIR /testbase