diff --git a/dll/steam_gameserver.cpp b/dll/steam_gameserver.cpp
index aa2d5072..1e9f7b5b 100644
--- a/dll/steam_gameserver.cpp
+++ b/dll/steam_gameserver.cpp
@@ -554,6 +554,8 @@ HAuthTicket Steam_GameServer::GetAuthSessionTicket( void *pTicket, int cbMaxTick
     PRINT_DEBUG("Steam_GameServer::GetAuthSessionTicket\n");
     std::lock_guard<std::recursive_mutex> lock(global_mutex);
 
+    if (!pTicket) return k_HAuthTicketInvalid;
+    
     return auth_manager->getTicket(pTicket, cbMaxTicket, pcbTicket);
 }
 
diff --git a/dll/steam_user.h b/dll/steam_user.h
index f2678fe6..c6659534 100644
--- a/dll/steam_user.h
+++ b/dll/steam_user.h
@@ -311,6 +311,8 @@ HAuthTicket GetAuthSessionTicket( void *pTicket, int cbMaxTicket, uint32 *pcbTic
     PRINT_DEBUG("Steam_User::GetAuthSessionTicket %i\n", cbMaxTicket);
     std::lock_guard<std::recursive_mutex> lock(global_mutex);
 
+    if (!pTicket) return k_HAuthTicketInvalid;
+    
     return auth_manager->getTicket(pTicket, cbMaxTicket, pcbTicket);
 }