MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases. From 3.0.0 until 3.3.7, 3.4.5, and 3.5.10, the ReadableByteBuf.readLength() and ReadableByteBuf.readIntLengthEncodedNotNull() methods narrowed the protocol's unsigned 8-byte length-encoded integer to a Java int without checking that the value fit a non-negative integer. Values above Integer.MAX_VALUE could wrap to a negative or unrelated length that downstream allocation and read paths used. A malicious or compromised server, or a machine-in-the-middle attacker, could trigger NegativeArraySizeException, out-of-bounds failures, or oversized allocation behavior in client connection handling. This issue is fixed in versions 3.3.7, 3.4.5, and 3.5.10.