From 66f7879c0fc4f2c0f74918baf01f36b6daf10653 Mon Sep 17 00:00:00 2001
From: klemek <klemek.dev@proton.me>
Date: Tue, 2 Jun 2026 22:05:16 +0200
Subject: [PATCH] fix(cert_manager): check host on SNI callback

---
 stapler/cert_manager.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stapler/cert_manager.py b/stapler/cert_manager.py
index 804cf6d..f553df6 100644
--- a/stapler/cert_manager.py
+++ b/stapler/cert_manager.py
@@ -192,7 +192,7 @@ class CertManager:
         _: ssl.SSLSocket,
         /,
     ) -> None | int:
-        if host is None:
+        if host is None or not valid_host(host):
             return None
         self.logger.debug("servername callback: %s", host)
         if not self.exists(host) and not self.create_or_update(host):