diff --git a/Dockerfile b/Dockerfile
index 3210bff..080b36a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM node:20.18.3-bullseye@sha256:eaf0b98ca475d59fcb5b6571fab3dc7486b74f4123672af4a8eddbb4c3f35a1e as build
+FROM node:21.7.3-bullseye@sha256:7374e262a514dd73abd4f0c1f960d7392f08d277feea19e6068980e7bfbcf414 as build
 
 # renovate: datasource=github-tags depName=gchq/CyberChef versioning=semver
 ENV CYBERCHEF_VERSION v10.19.4