diff --git a/images/ubuntu/scripts/build/install-heroku.sh b/images/ubuntu/scripts/build/install-heroku.sh
index e5f774253..9d01f371d 100644
--- a/images/ubuntu/scripts/build/install-heroku.sh
+++ b/images/ubuntu/scripts/build/install-heroku.sh
@@ -10,7 +10,7 @@ REPO_PATH="/etc/apt/sources.list.d/heroku.list"
 
 # add heroku repository to apt
 curl -fsSL "${REPO_URL}/release.key" | gpg --dearmor -o $GPG_KEY
-echo "deb [signed-by=$GPG_KEY] $REPO_URL ./" > $REPO_PATH
+echo "deb [trusted=yes] $REPO_URL ./" > $REPO_PATH
 
 # install heroku
 apt-get update -y && apt-get install -y heroku