CVE-2026-55858

Описание

MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases. Prior to 2.7.14, 3.3.5, 3.4.3, and 3.5.9, the connector encodes and decodes protocol text and performs client-side escaping under the assumption that the connection character set is UTF-8. The server can report a mid-session change to character_set_client through OK-packet session-state tracking, including a change caused by SET NAMES, a stored routine or trigger, server configuration, or a hostile server. If character_set_client changes to a non-UTF-8 value, the driver continues to read and write UTF-8 while the server interprets the same bytes under another encoding, causing silent data corruption and a client/server charset-confusion mismatch that can defeat byte-wise quoting or escaping. The fix accepts only utf8, utf8mb3, or utf8mb4 after initialization; any other value causes SQLException with SQLState 08000 and closes the connection. This issue is fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9.

A flaw was found in MariaDB Connector/J, a component used to connect Java applications to MariaDB and MySQL databases. The connector incorrectly assumes a UTF-8 character set for communication, even if the database server changes its client character set to a non-UTF-8 value during a session. This mismatch can lead to silent data corruption, where data is written and read incorrectly, and may also allow attackers to bypass security mechanisms like byte-wise quoting or escaping.