diff --git a/package/debian/prometheus-dnssec-exporter/DEBIAN/postinst b/package/debian/prometheus-dnssec-exporter/DEBIAN/postinst
index bc5c5c2..8807530 100755
--- a/package/debian/prometheus-dnssec-exporter/DEBIAN/postinst
+++ b/package/debian/prometheus-dnssec-exporter/DEBIAN/postinst
@@ -14,7 +14,7 @@ if [[ "$1" == "configure" ]]; then
 
     chown root:prometheus /etc/prometheus/dnssec-exporter /etc/prometheus/dnssec-exporter/config.yaml
     chmod 0755 /etc/prometheus/dnssec-exporter
-    cmmod 0640 /etc/prometheus/dnssec-exporter/config.yaml
+    chmod 0640 /etc/prometheus/dnssec-exporter/config.yaml
 
     deb-systemd-helper enable prometheus-dnssec-exporter.service
     deb-systemd-invoke restart prometheus-dnssec-exporter.service