diff --git a/files/core_alerts.yml b/files/core_alerts.yml
index 08580e9afa33f2b418f986518395718145159a76..e312ecb5e005f8dc0c2d5da4bf647c6b6e977c87 100644
--- a/files/core_alerts.yml
+++ b/files/core_alerts.yml
@@ -188,7 +188,7 @@ groups:
       summary: "Certificate (instance {{ $labels.instance }})"
       description: "Certificate more than 70% expired.\n  VALUE = {{ $value }}\n  LABELS: {{ $labels }}"
   - alert: CertificateExpirationCritical
-    expr: ((quantile by (serial_no,cn,instance) (0.5, ssl_cert_not_after)) and ((quantile by (serial_no,cn,instance) (0.5, ((ssl_cert_not_after - time()) /  (ssl_cert_not_after - ssl_cert_not_before))) ) < 0.2)) - time()
+    expr: ((quantile by (serial_no,cn,instance) (0.5, ssl_cert_not_after)) and ((quantile by (serial_no,cn,instance) (0.5, ((ssl_cert_not_after{serial_no!="14430537077252496941928767712285731324"} - time()) /  (ssl_cert_not_after - ssl_cert_not_before))) ) < 0.2)) - time()
     for: 2m
     labels:
       severity: critical