diff --git a/hack/tools/gen-matrix.sh b/hack/tools/gen-matrix.sh
index fed9903b3e76..90d17f199a17 100755
--- a/hack/tools/gen-matrix.sh
+++ b/hack/tools/gen-matrix.sh
@@ -1,14 +1,16 @@
-#!/usr/bin/env sh
+#!/usr/bin/env bash
 
 # Finds the last k0s releases of the given versions and generates json MATRIX_OUTPUT for github actions.
 # Usage:
 #  ./gen-matrix.sh 1.24.2 1.24.3
 # Output: ["v1.24.2+k0s.0", "v1.24.3+k0s.0"]
 
+set -e -o pipefail
+
 list_k0s_releases() {
-  gh api -X GET /repos/k0sproject/k0s/releases \
-    -F per_page=100 --paginate \
-    --jq '.[] | select(.prerelease == false and .draft == false) | .name'
+  # shellcheck disable=SC2016
+  local query='.[] | select(.prerelease == false and .draft == false) | .name | select(startswith($ENV.VERSION_PREFIX))'
+  VERSION_PREFIX="v$1" gh api -X GET /repos/k0sproject/k0s/releases -F per_page=100 --paginate --jq "$query"
 }
 
 k0s_sort() {
@@ -16,7 +18,7 @@ k0s_sort() {
 }
 
 latest_release() {
-  list_k0s_releases | grep -F "v$1" | k0s_sort | tail -1
+  list_k0s_releases "$1" | k0s_sort | tail -1
 }
 
 json_print_latest_releases() {