diff --git a/Dockerfile b/Dockerfile
index 97b987a..4c54272 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # Build the manager binary
-FROM golang:1.21 as builder
+FROM golang:1.25@sha256:20b91eda7a9627c127c0225b0d4e8ec927b476fa4130c6760928b849d769c149 as builder
 
 WORKDIR /workspace
 # Copy the Go Modules manifests