diff --git a/include/pam_authenticate.hpp b/include/pam_authenticate.hpp
index 59c8cd6..f2c7356 100644
--- a/include/pam_authenticate.hpp
+++ b/include/pam_authenticate.hpp
@@ -23,7 +23,7 @@
         return PAM_AUTH_ERR;
     }
 
-    std::strcpy(pass, appPass);
+    std::strncpy(pass, appPass, appPassSize + 1);
 
     *resp = reinterpret_cast<pam_response*>(
         calloc(static_cast<size_t>(numMsg), sizeof(struct pam_response)));