diff --git a/src/unlocker/main.cpp b/src/unlocker/main.cpp
index 9565400..6432381 100644
--- a/src/unlocker/main.cpp
+++ b/src/unlocker/main.cpp
@@ -47,6 +47,8 @@ Proxy* g_Proxy = nullptr;
 
 void cleanup()
 {
+    static std::mutex cleanupMutex;
+    std::lock_guard<std::mutex> lock(cleanupMutex);
     static bool cleaned = false;
     if (cleaned) return;
     cleaned = true;