diff --git a/src/test-device/Dockerfile b/src/test-device/Dockerfile
index f1be877..23507c1 100644
--- a/src/test-device/Dockerfile
+++ b/src/test-device/Dockerfile
@@ -1,6 +1,6 @@
 # https://hub.docker.com/r/qemux/qemu-docker
 # https://github.com/qemus/qemu-docker
-FROM qemux/qemu-docker:6.19
+FROM qemux/qemu-docker:6.20
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
 	minicom \