diff --git a/Dockerfile b/Dockerfile
index 63bfc7ba..543f2d29 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,7 @@
 ### BUILDER STAGE
 #
 #
-FROM golang:1.26-alpine AS builder
+FROM golang:1.26-alpine3.23 AS builder
 
 # Do not remove `git` here, it is required for getting runner version when executing `make build`
 RUN apk add --no-cache make git
@@ -17,7 +17,7 @@ RUN make clean && make build
 ### DIND VARIANT
 #
 #
-FROM docker:29-dind AS dind
+FROM docker:29.5.2-dind AS dind
 
 ARG VERSION=dev
 
@@ -37,7 +37,7 @@ ENTRYPOINT ["s6-svscan","/etc/s6"]
 ### DIND-ROOTLESS VARIANT
 #
 #
-FROM docker:29-dind-rootless AS dind-rootless
+FROM docker:29.5.2-dind-rootless AS dind-rootless
 
 ARG VERSION=dev
 
@@ -63,7 +63,7 @@ ENTRYPOINT ["s6-svscan","/etc/s6"]
 ### BASIC VARIANT
 #
 #
-FROM alpine AS basic
+FROM alpine:3.23 AS basic
 
 ARG VERSION=dev
 
diff --git a/act/runner/testdata/actions-environment-and-context-tests/docker/Dockerfile b/act/runner/testdata/actions-environment-and-context-tests/docker/Dockerfile
index bd8fcb22..2471eac3 100644
--- a/act/runner/testdata/actions-environment-and-context-tests/docker/Dockerfile
+++ b/act/runner/testdata/actions-environment-and-context-tests/docker/Dockerfile
@@ -1,4 +1,4 @@
-FROM alpine:3
+FROM alpine:3.23
 
 COPY entrypoint.sh /entrypoint.sh