From 43157a1d37d3d87cfac1057b48a4c36474a2271d Mon Sep 17 00:00:00 2001
From: 5tuk0v <90915844+5tuk0v@users.noreply.github.com>
Date: Sat, 21 Feb 2026 22:48:23 -0500
Subject: [PATCH] fix: restore compatibility with modern Windows Update clients
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Remove hardcoded Prerequisites category UUID (0fa1201d) from
  sync-updates.xml — modern WU clients no longer satisfy this category,
  causing updates to be silently marked non-applicable
- Populate <Properties> in get-config.xml with required protocol
  negotiation fields (ProtocolVersion, MaxExtendedUpdatesPerRequest,
  IsInventoryRequired, ClientReportingLevel) — absence causes 0x8024402a
  on current WU client versions
- Catch ConnectionResetError/BrokenPipeError on EXE send in do_GET —
  suppresses noisy traceback from BITS range-request probe
- Bump lxml to >=4.9.2 to fix build failure on Python 3.11+

Tested on: Windows 10 22H2, Windows 11 24H2, Windows Server 2019, Windows Server 2022
---
 pywsus.py                  | 5 ++++-
 requirements.txt           | 2 +-
 resources/get-config.xml   | 2 +-
 resources/sync-updates.xml | 2 +-
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/pywsus.py b/pywsus.py
index 21ee579..a090681 100644
--- a/pywsus.py
+++ b/pywsus.py
@@ -140,7 +140,10 @@ def do_GET(self):
             logging.info("Requested: {path}".format(path=self.path))
 
             self._set_response(True)
-            self.wfile.write(update_handler.executable)
+            try:
+                self.wfile.write(update_handler.executable)
+            except (ConnectionResetError, BrokenPipeError):
+                logging.debug("Connection reset during EXE send (BITS probe, normal)")
 
     def do_POST(self):
 
diff --git a/requirements.txt b/requirements.txt
index 79e47c6..e4c98a5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
 beautifulsoup4==4.9.1
-lxml==4.6.2
+lxml>=4.9.2
 soupsieve==2.0.1
diff --git a/resources/get-config.xml b/resources/get-config.xml
index 9fa5bf2..5276315 100644
--- a/resources/get-config.xml
+++ b/resources/get-config.xml
@@ -1 +1 @@
-<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"><s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><GetConfigResponse xmlns="http://www.microsoft.com/SoftwareDistribution/Server/ClientWebService"><GetConfigResult><LastChange>{lastChange}</LastChange><IsRegistrationRequired>false</IsRegistrationRequired><AuthInfo><AuthPlugInInfo><PlugInID>Anonymous</PlugInID><ServiceUrl/><Parameter/></AuthPlugInInfo></AuthInfo><Properties/></GetConfigResult></GetConfigResponse></s:Body></s:Envelope>
+<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"><s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><GetConfigResponse xmlns="http://www.microsoft.com/SoftwareDistribution/Server/ClientWebService"><GetConfigResult><LastChange>{lastChange}</LastChange><IsRegistrationRequired>false</IsRegistrationRequired><AuthInfo><AuthPlugInInfo><PlugInID>Anonymous</PlugInID><ServiceUrl/><Parameter/></AuthPlugInInfo></AuthInfo><Properties><ConfigurationProperty><Name>ProtocolVersion</Name><Value>3.2</Value></ConfigurationProperty><ConfigurationProperty><Name>MaxExtendedUpdatesPerRequest</Name><Value>20</Value></ConfigurationProperty><ConfigurationProperty><Name>IsInventoryRequired</Name><Value>0</Value></ConfigurationProperty><ConfigurationProperty><Name>ClientReportingLevel</Name><Value>2</Value></ConfigurationProperty></Properties></GetConfigResult></GetConfigResponse></s:Body></s:Envelope>
diff --git a/resources/sync-updates.xml b/resources/sync-updates.xml
index 09e607f..f45ece6 100644
--- a/resources/sync-updates.xml
+++ b/resources/sync-updates.xml
@@ -1 +1 @@
-<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"><s:Body xmlns:xsi="http://www.w4.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><SyncUpdatesResponse xmlns="http://www.microsoft.com/SoftwareDistribution/Server/ClientWebService"><SyncUpdatesResult><NewUpdates><UpdateInfo><ID>{revision_id1}</ID><Deployment><ID>{deployment_id1}</ID><Action>Install</Action><IsAssigned>true</IsAssigned><LastChangeTime>2020-02-29</LastChangeTime><AutoSelect>0</AutoSelect><AutoDownload>0</AutoDownload><SupersedenceBehavior>0</SupersedenceBehavior></Deployment><IsLeaf>true</IsLeaf><Xml>&lt;UpdateIdentity UpdateID="{uuid1}" RevisionNumber="204" /&gt;&lt;Properties UpdateType="Software" ExplicitlyDeployable="true" AutoSelectOnWebSites="true" /&gt;&lt;Relationships&gt;&lt;Prerequisites&gt;&lt;AtLeastOne IsCategory="true"&gt;&lt;UpdateIdentity UpdateID="0fa1201d-4330-4fa8-8ae9-b877473b6441" /&gt;&lt;/AtLeastOne&gt;&lt;/Prerequisites&gt;&lt;BundledUpdates&gt;&lt;UpdateIdentity UpdateID="{uuid2}" RevisionNumber="204" /&gt;&lt;/BundledUpdates&gt;&lt;/Relationships&gt;</Xml></UpdateInfo><UpdateInfo><ID>{revision_id2}</ID><Deployment><ID>{deployment_id2}</ID><Action>Bundle</Action><IsAssigned>true</IsAssigned><LastChangeTime>2020-02-29</LastChangeTime><AutoSelect>0</AutoSelect><AutoDownload>0</AutoDownload><SupersedenceBehavior>0</SupersedenceBehavior></Deployment><IsLeaf>true</IsLeaf><Xml>&lt;UpdateIdentity UpdateID="{uuid2}" RevisionNumber="204" /&gt;&lt;Properties UpdateType="Software" /&gt;&lt;Relationships&gt;&lt;/Relationships&gt;&lt;ApplicabilityRules&gt;&lt;IsInstalled&gt;&lt;False /&gt;&lt;/IsInstalled&gt;&lt;IsInstallable&gt;&lt;True /&gt;&lt;/IsInstallable&gt;&lt;/ApplicabilityRules&gt;</Xml></UpdateInfo></NewUpdates><Truncated>false</Truncated><NewCookie><Expiration>{expire}</Expiration><EncryptedData>{cookie}</EncryptedData></NewCookie><DriverSyncNotNeeded>true</DriverSyncNotNeeded></SyncUpdatesResult></SyncUpdatesResponse></s:Body></s:Envelope>
+<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"><s:Body xmlns:xsi="http://www.w4.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><SyncUpdatesResponse xmlns="http://www.microsoft.com/SoftwareDistribution/Server/ClientWebService"><SyncUpdatesResult><NewUpdates><UpdateInfo><ID>{revision_id1}</ID><Deployment><ID>{deployment_id1}</ID><Action>Install</Action><IsAssigned>true</IsAssigned><LastChangeTime>2020-02-29</LastChangeTime><AutoSelect>0</AutoSelect><AutoDownload>0</AutoDownload><SupersedenceBehavior>0</SupersedenceBehavior></Deployment><IsLeaf>true</IsLeaf><Xml>&lt;UpdateIdentity UpdateID="{uuid1}" RevisionNumber="204" /&gt;&lt;Properties UpdateType="Software" ExplicitlyDeployable="true" AutoSelectOnWebSites="true" /&gt;&lt;Relationships&gt;&lt;BundledUpdates&gt;&lt;UpdateIdentity UpdateID="{uuid2}" RevisionNumber="204" /&gt;&lt;/BundledUpdates&gt;&lt;/Relationships&gt;</Xml></UpdateInfo><UpdateInfo><ID>{revision_id2}</ID><Deployment><ID>{deployment_id2}</ID><Action>Bundle</Action><IsAssigned>true</IsAssigned><LastChangeTime>2020-02-29</LastChangeTime><AutoSelect>0</AutoSelect><AutoDownload>0</AutoDownload><SupersedenceBehavior>0</SupersedenceBehavior></Deployment><IsLeaf>true</IsLeaf><Xml>&lt;UpdateIdentity UpdateID="{uuid2}" RevisionNumber="204" /&gt;&lt;Properties UpdateType="Software" /&gt;&lt;Relationships&gt;&lt;/Relationships&gt;&lt;ApplicabilityRules&gt;&lt;IsInstalled&gt;&lt;False /&gt;&lt;/IsInstalled&gt;&lt;IsInstallable&gt;&lt;True /&gt;&lt;/IsInstallable&gt;&lt;/ApplicabilityRules&gt;</Xml></UpdateInfo></NewUpdates><Truncated>false</Truncated><NewCookie><Expiration>{expire}</Expiration><EncryptedData>{cookie}</EncryptedData></NewCookie><DriverSyncNotNeeded>true</DriverSyncNotNeeded></SyncUpdatesResult></SyncUpdatesResponse></s:Body></s:Envelope>