diff --git a/.github/workflows/delete-old-workflow-runs.yml b/.github/workflows/delete-old-workflow-runs.yml
new file mode 100644
index 00000000..29f9ca05
--- /dev/null
+++ b/.github/workflows/delete-old-workflow-runs.yml
@@ -0,0 +1,18 @@
+name: Delete old workflow runs
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '0 0 1 * *'
+# Run monthly, at 00:00 on the 1st day of month.
+
+jobs:
+  del_runs:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Delete workflow runs
+        uses: Mattraks/delete-workflow-runs@v2
+        with:
+          token: ${{ github.token }}
+          repository: ${{ github.repository }}
+          retain_days: 30
+          keep_minimum_runs: 6
diff --git a/plugins/dynamic-security/plugin.c b/plugins/dynamic-security/plugin.c
index 3ff1054a..980a3415 100644
--- a/plugins/dynamic-security/plugin.c
+++ b/plugins/dynamic-security/plugin.c
@@ -452,7 +452,7 @@ void dynsec__config_save(void)
 
 	/* Save to file */
 	file_path_len = strlen(config_file) + 1;
-	file_path = mosquitto_malloc(file_path_len);
+	file_path = mosquitto_malloc(file_path_len + 4);
 	if(file_path == NULL){
 		mosquitto_free(json_str);
 		mosquitto_log_printf(MOSQ_LOG_ERR, "Error saving Dynamic security plugin config: Out of memory.\n");