diff --git a/passphrase_cache.cc b/passphrase_cache.cc
index c7dad6f..4019a61 100644
--- a/passphrase_cache.cc
+++ b/passphrase_cache.cc
@@ -48,7 +48,7 @@ namespace pEp {
 
     const char *PassphraseCache::add_stored(const std::string& passphrase)
     {
-        std::lock_guard<std::mutex> lock(_shared_mtx);
+        std::lock_guard<std::mutex> lock(_stored_mtx);
         _stored = passphrase;
         return _stored.c_str();
     }
@@ -59,7 +59,7 @@ namespace pEp {
             return true;
 
         {
-            std::lock_guard<std::mutex> lock(_shared_mtx);
+            std::lock_guard<std::mutex> lock(_stored_mtx);
             if (!_stored.empty() && callee(_stored))
                 return true;
         }
diff --git a/passphrase_cache.hh b/passphrase_cache.hh
index 3a82655..13121e9 100644
--- a/passphrase_cache.hh
+++ b/passphrase_cache.hh
@@ -26,7 +26,7 @@ namespace pEp {
         cache _cache;
         std::string _stored;
         std::mutex _mtx;
-        std::mutex _shared_mtx;
+        std::mutex _stored_mtx;
         size_t _max_size;
         duration _timeout;