diff --git a/conformance/Dockerfile b/conformance/Dockerfile
index c113d3810e..d34caa3646 100644
--- a/conformance/Dockerfile
+++ b/conformance/Dockerfile
@@ -1,4 +1,4 @@
-FROM alpine:3.20
+FROM alpine:3.21
 ENV SONOBUOY_VERSION 0.57.2
 RUN apk add curl tar gzip
 RUN curl -sfL https://github.com/vmware-tanzu/sonobuoy/releases/download/v${SONOBUOY_VERSION}/sonobuoy_${SONOBUOY_VERSION}_linux_amd64.tar.gz | tar xvzf - -C /usr/bin