diff --git a/src/docker.ts b/src/docker.ts
index 2efff207..61708f42 100644
--- a/src/docker.ts
+++ b/src/docker.ts
@@ -1,7 +1,7 @@
 class Docker {
   readonly repository = 'renovate/renovate';
   // renovate: datasource=docker depName=renovate/renovate versioning=docker
-  readonly tag = '25.20.1-slim';
+  readonly tag = '25.21.1-slim';
   readonly tagSuffix = '-slim';
 
   image(): string {