mgr/alerts: enforce ssl context to SMTP_SSL

Fixes: https://github.com/ceph/ceph/security/advisories/GHSA-xj9f-7g59-m4jx
Signed-off-by: Nizamudeen A <[email protected]>

Author: nizamial09

src/pybind/mgr/alerts/module.py

@@ -9,6 +9,7 @@
 from typing import Any, Optional, Dict, List, TYPE_CHECKING, Union
 import json
 import smtplib
+import ssl
 
 
 class Alerts(MgrModule):
@@ -236,9 +237,10 @@ def _send_alert_smtp(self,
 
         # send
         try:
+            context = ssl.create_default_context()
             if self.smtp_ssl:
                 server: Union[smtplib.SMTP_SSL, smtplib.SMTP] = \
-                    smtplib.SMTP_SSL(self.smtp_host, self.smtp_port)
+                    smtplib.SMTP_SSL(self.smtp_host, self.smtp_port, context=context)
             else:
                 server = smtplib.SMTP(self.smtp_host, self.smtp_port)
             if self.smtp_password: