diff --git a/GuardDutyToSlack/requirements.txt b/GuardDutyToSlack/requirements.txt
index 663bd1f..f6eb028 100644
--- a/GuardDutyToSlack/requirements.txt
+++ b/GuardDutyToSlack/requirements.txt
@@ -1 +1,2 @@
-requests
\ No newline at end of file
+requests
+certifi>=2023.7.22 # not directly required, pinned by Snyk to avoid a vulnerability
\ No newline at end of file