diff --git a/cmd/testdata/testsvc/Dockerfile b/cmd/testdata/testsvc/Dockerfile
index 6f222d77..b66c81d3 100644
--- a/cmd/testdata/testsvc/Dockerfile
+++ b/cmd/testdata/testsvc/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.24.2-alpine AS builder
+FROM golang:1.26rc1-alpine AS builder
 
 ENV GO111MODULE=on
 ARG user