diff --git a/Dockerfile b/Dockerfile
index dd38ee945..8d6b367aa 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,7 +3,7 @@
 # Copyright 2020-2023 the Pinniped contributors. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-ARG BUILD_IMAGE=golang:1.21.4
+ARG BUILD_IMAGE=golang:1.21.4@sha256:81cd210ae58a6529d832af2892db822b30d84f817a671b8e1c15cff0b271a3db
 ARG BASE_IMAGE=gcr.io/distroless/static@sha256:91ca4720011393f4d4cab3a01fa5814ee2714b7d40e6c74f2505f74168398ca9
 
 # Prepare to cross-compile by always running the build stage in the build platform, not the target platform.
diff --git a/hack/Dockerfile_fips b/hack/Dockerfile_fips
index c46ef70b0..7921bdbfb 100644
--- a/hack/Dockerfile_fips
+++ b/hack/Dockerfile_fips
@@ -16,7 +16,7 @@
 # See https://go.googlesource.com/go/+/dev.boringcrypto/README.boringcrypto.md
 # and https://kupczynski.info/posts/fips-golang/ for details.
 
-ARG BUILD_IMAGE=golang:1.21.4
+ARG BUILD_IMAGE=golang:1.21.4@sha256:81cd210ae58a6529d832af2892db822b30d84f817a671b8e1c15cff0b271a3db
 ARG BASE_IMAGE=gcr.io/distroless/static@sha256:91ca4720011393f4d4cab3a01fa5814ee2714b7d40e6c74f2505f74168398ca9
 
 # This is not currently using --platform to prepare to cross-compile because we use gcc below to build