diff --git a/hack/libhack/challenge.sh b/hack/libhack/challenge.sh
index f65f7ee..e602688 100644
--- a/hack/libhack/challenge.sh
+++ b/hack/libhack/challenge.sh
@@ -44,9 +44,9 @@ challenge::run() {
         mount_volumes="${mount_baseimage:-} ${mount_challenge}"
     fi
     popd
-    docker run --rm                                          \
-               -p ${CHALLENGE_PORT}:${CHALLENGE_PORT}        \
-               ${mount_volumes:-}                            \
-               ${@:-}                                        \
+    docker run --rm                                             \
+               -p 127.0.0.1:${CHALLENGE_PORT}:${CHALLENGE_PORT} \
+               ${mount_volumes:-}                               \
+               ${@:-}                                           \
                -e AVATAO_SECRET="${AVATAO_SECRET}" ${IMAGE_NAME}
 }