From 99ffd88c5562c5fb023c568ac1bfa1fd9e4651cb Mon Sep 17 00:00:00 2001
From: A13501350 <18516149786@163.com>
Date: Thu, 27 Aug 2026 16:46:34 +0800
Subject: [PATCH] Fix IIS Host header fallback: treat empty r->hostname like
 NULL

---
 iis/mymodule.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/iis/mymodule.cpp b/iis/mymodule.cpp
index dfaee4b2cb..061ad7d684 100644
--- a/iis/mymodule.cpp
+++ b/iis/mymodule.cpp
@@ -840,7 +840,7 @@ CMyHttpModule::OnBeginRequest(
 	r->hostname = ConvertUTF16ToUTF8(req->CookedUrl.pHost, req->CookedUrl.HostLength / sizeof(WCHAR), r->pool);
 	r->path_info = ConvertUTF16ToUTF8(req->CookedUrl.pAbsPath, req->CookedUrl.AbsPathLength / sizeof(WCHAR), r->pool);
 
-	if(r->hostname == NULL)
+	if(r->hostname == NULL || r->hostname[0] == '\0')
 	{
 		if(req->Headers.KnownHeaders[HttpHeaderHost].pRawValue != NULL)
 			r->hostname = ZeroTerminate(req->Headers.KnownHeaders[HttpHeaderHost].pRawValue,