diff --git a/integration/Dockerfile b/integration/Dockerfile
index 0535db398d..1047766e56 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:buster@sha256:eb3f9ac805435c1b2c965d63ce460988e1000058e1f67881324746362baf9572 as ct_testbase
+FROM golang:1.21.1-bookworm@sha256:d3114db136e7f2d9b08c3fcd374381ba3f8d85c17b80c48dbc53cd938cfb2b64 as ct_testbase
 
 WORKDIR /testbase
 
diff --git a/internal/witness/cmd/feeder/Dockerfile b/internal/witness/cmd/feeder/Dockerfile
index 39dd2a19c6..07c8aca5de 100644
--- a/internal/witness/cmd/feeder/Dockerfile
+++ b/internal/witness/cmd/feeder/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.21-alpine@sha256:96634e55b363cb93d39f78fb18aa64abc7f96d372c176660d7b8b6118939d97b AS builder
+FROM golang:1.21.1-bookworm@sha256:d3114db136e7f2d9b08c3fcd374381ba3f8d85c17b80c48dbc53cd938cfb2b64 as builder
 
 ARG GOFLAGS=""
 ENV GOFLAGS=$GOFLAGS
diff --git a/internal/witness/cmd/witness/Dockerfile b/internal/witness/cmd/witness/Dockerfile
index 3889349642..a59ad7b8a5 100644
--- a/internal/witness/cmd/witness/Dockerfile
+++ b/internal/witness/cmd/witness/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:buster@sha256:eb3f9ac805435c1b2c965d63ce460988e1000058e1f67881324746362baf9572 AS builder
+FROM golang:1.21.1-bookworm@sha256:d3114db136e7f2d9b08c3fcd374381ba3f8d85c17b80c48dbc53cd938cfb2b64 AS builder
 
 ARG GOFLAGS=""
 ENV GOFLAGS=$GOFLAGS
@@ -18,7 +18,7 @@ COPY . .
 RUN go build -o /build/bin/witness ./internal/witness/cmd/witness
 
 # Build release image
-FROM golang:buster@sha256:eb3f9ac805435c1b2c965d63ce460988e1000058e1f67881324746362baf9572
+FROM golang:1.21.1-bookworm@sha256:d3114db136e7f2d9b08c3fcd374381ba3f8d85c17b80c48dbc53cd938cfb2b64
 
 COPY --from=builder /build/bin/witness /bin/witness
 ENTRYPOINT ["/bin/witness"]
diff --git a/trillian/examples/deployment/docker/ctfe/Dockerfile b/trillian/examples/deployment/docker/ctfe/Dockerfile
index 437acab61a..dffa4adc9b 100644
--- a/trillian/examples/deployment/docker/ctfe/Dockerfile
+++ b/trillian/examples/deployment/docker/ctfe/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:buster@sha256:eb3f9ac805435c1b2c965d63ce460988e1000058e1f67881324746362baf9572 as build
+FROM golang:1.21.1-bookworm@sha256:d3114db136e7f2d9b08c3fcd374381ba3f8d85c17b80c48dbc53cd938cfb2b64 as build
 
 ARG GOFLAGS=""
 ENV GOFLAGS=$GOFLAGS