diff --git a/appengine/flexible/mailjet/requirements.txt b/appengine/flexible/mailjet/requirements.txt
index 024a4aaf232..f22a5915f23 100644
--- a/appengine/flexible/mailjet/requirements.txt
+++ b/appengine/flexible/mailjet/requirements.txt
@@ -2,3 +2,4 @@ Flask==1.0.2
 gunicorn==19.9.0
 requests[security]==2.21.0
 mailjet-rest==1.3.0
+urllib3>=2.6.0 # not directly required, pinned by Snyk to avoid a vulnerability