diff --git a/base-foc/src/base/env/cap_map.cc b/base-foc/src/base/env/cap_map.cc
index c63d21c99..db31ab107 100644
--- a/base-foc/src/base/env/cap_map.cc
+++ b/base-foc/src/base/env/cap_map.cc
@@ -89,8 +89,12 @@ void Genode::Capability_map::remove(Genode::Cap_index* i)
 	Lock_guard<Spin_lock> guard(_lock);
 
 	if (i) {
-		_tree.remove(i);
-		cap_idx_alloc()->free(i,1);
+		if (_tree.first())
+			i = _tree.first()->find_by_id(i->id());
+		if (i) {
+			_tree.remove(i);
+			cap_idx_alloc()->free(i,1);
+		}
 	}
 }
 
diff --git a/base-foc/src/core/cap_session_component.cc b/base-foc/src/core/cap_session_component.cc
index 4703bc768..8c188775a 100644
--- a/base-foc/src/core/cap_session_component.cc
+++ b/base-foc/src/core/cap_session_component.cc
@@ -92,7 +92,7 @@ Cap_mapping::Cap_mapping(Core_cap_index* i, Native_thread_id r)
 Cap_mapping::~Cap_mapping()
 {
 	unmap();
-	cap_map()->remove(cap_map()->find(local->id()));
+	cap_map()->remove(local);
 }