diff --git a/lib/MySQL_Protocol.cpp b/lib/MySQL_Protocol.cpp
index c33bafac0..27caba7ca 100644
--- a/lib/MySQL_Protocol.cpp
+++ b/lib/MySQL_Protocol.cpp
@@ -2038,7 +2038,8 @@ __do_auth:
 									proxy_error("Unable to load credentials for backend user %s , associated to LDAP user %s\n", backend_username, user);
 								}
 							} else {
-								ret=true;
+								proxy_error("Unable to find backend user associated to LDAP user '%s'\n", user);
+								ret=false;
 							}
 						}
 					}
diff --git a/lib/MySQL_Session.cpp b/lib/MySQL_Session.cpp
index b10caeb03..c5be72dba 100644
--- a/lib/MySQL_Session.cpp
+++ b/lib/MySQL_Session.cpp
@@ -641,7 +641,11 @@ MySQL_Session::~MySQL_Session() {
 					break;
 #endif /* PROXYSQLCLICKHOUSE */
 				default:
-					GloMyAuth->decrease_frontend_user_connections(client_myds->myconn->userinfo->username);
+					if (use_ldap_auth == false) {
+						GloMyAuth->decrease_frontend_user_connections(client_myds->myconn->userinfo->username);
+					} else {
+						GloMyLdapAuth->decrease_frontend_user_connections(client_myds->myconn->userinfo->fe_username);
+					}
 					break;
 			}
 		}
diff --git a/lib/ProxySQL_Admin.cpp b/lib/ProxySQL_Admin.cpp
index 6bb1e9f29..2862efc8b 100644
--- a/lib/ProxySQL_Admin.cpp
+++ b/lib/ProxySQL_Admin.cpp
@@ -1760,12 +1760,12 @@ bool is_valid_global_variable(const char *var_name) {
 		return true;
 	} else if (strlen(var_name) > 6 && !strncmp(var_name, "admin-", 6) && SPA->has_variable(var_name + 6)) {
 		return true;
-	} else if (strlen(var_name) > 5 && !strncmp(var_name, "ldap-", 5) && GloMyLdapAuth->has_variable(var_name + 5)) {
+	} else if (strlen(var_name) > 5 && !strncmp(var_name, "ldap-", 5) && GloMyLdapAuth && GloMyLdapAuth->has_variable(var_name + 5)) {
 		return true;
-	} else if (strlen(var_name) > 13 && !strncmp(var_name, "sqliteserver-", 13) && GloSQLite3Server->has_variable(var_name + 13)) {
+	} else if (strlen(var_name) > 13 && !strncmp(var_name, "sqliteserver-", 13) && GloSQLite3Server && GloSQLite3Server->has_variable(var_name + 13)) {
 		return true;
 #ifdef PROXYSQLCLICKHOUSE
-	} else if (strlen(var_name) > 11 && !strncmp(var_name, "clickhouse-", 11) && GloClickHouseServer->has_variable(var_name + 11)) {
+	} else if (strlen(var_name) > 11 && !strncmp(var_name, "clickhouse-", 11) && GloClickHouseServer && GloClickHouseServer->has_variable(var_name + 11)) {
 		return true;
 #endif /* PROXYSQLCLICKHOUSE */
 	} else {
diff --git a/lib/sqlite3db.cpp b/lib/sqlite3db.cpp
index d97ccf485..e839ef211 100644
--- a/lib/sqlite3db.cpp
+++ b/lib/sqlite3db.cpp
@@ -730,7 +730,7 @@ void SQLite3DB::LoadPlugin(const char *plugin_name) {
 					SHA1(fb, statbuf.st_size, temp);
 					memset(binary_sha1_sqlite3, 0, SHA_DIGEST_LENGTH*2+1);
 					char buf[SHA_DIGEST_LENGTH*2];
-					for (int i=0; i < SHA_DIGEST_LENGTH; i++) {
+					for (int i=0; i < SHA_DIGEST_LENGTH - 1; i++) {
 						sprintf((char*)&(buf[i*2]), "%02x", temp[i]);
 					}
 					memcpy(binary_sha1_sqlite3, buf, SHA_DIGEST_LENGTH*2);