From e8d9158a537c20fe92d45495d10db2b9b051944c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lukas=20Br=C3=BCbach?= <Bruebach.Lukas@bdosecurity.de>
Date: Mon, 21 Sep 2026 18:46:25 +0200
Subject: [PATCH] [Windows] Verify the force close and abort if the process
 survived

---
 cmake/NSIS.template.in | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/cmake/NSIS.template.in b/cmake/NSIS.template.in
index d044cfd81..79f858cfd 100644
--- a/cmake/NSIS.template.in
+++ b/cmake/NSIS.template.in
@@ -298,6 +298,15 @@ Function WaitForAppToClose
         DetailPrint "Force closing $R1 ..."
         Call ForceCloseMatchingApps
         Sleep 500
+        ; verify the force close actually worked; a process that cannot be
+        ; terminated (e.g. one owned by another user session) would otherwise
+        ; leave locked files that silently reproduce the very mixed-Qt-DLL bug
+        ; this guard exists to prevent.
+        Call IsAppRunning
+        ${If} $R0 = 1
+            DetailPrint "WARNING: $R1 is still running; aborting before any files are replaced."
+            Abort
+        ${EndIf}
     ${Else}
         ck_wait_prompt:
         MessageBox MB_RETRYCANCEL|MB_ICONEXCLAMATION|MB_DEFBUTTON1 \
@@ -387,6 +396,15 @@ Function un.WaitForAppToClose
         DetailPrint "Force closing $R1 ..."
         Call un.ForceCloseMatchingApps
         Sleep 500
+        ; verify the force close actually worked; a process that cannot be
+        ; terminated (e.g. one owned by another user session) would otherwise
+        ; leave locked files that silently reproduce the very mixed-Qt-DLL bug
+        ; this guard exists to prevent.
+        Call un.IsAppRunning
+        ${If} $R0 = 1
+            DetailPrint "WARNING: $R1 is still running; aborting before any files are replaced."
+            Abort
+        ${EndIf}
     ${Else}
         un_ck_wait_prompt:
         MessageBox MB_RETRYCANCEL|MB_ICONEXCLAMATION|MB_DEFBUTTON1 \