CVE-2026-55857: MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases.

MariaDB Connector/J is used to connect applications developed in Java to MariaDB and MySQL databases.

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, PAM dialog authentication can be coerced into transmitting the account password over an insecure connection. The mysql_clear_password plugin is gated behind a secure transport, but the sibling PAM handler SendPamAuthPacketFactory, named dialog by the server, does not declare that requirement and inherits the default secure-required value false; older branches implement the same affected behavior in SendPamAuthPacket. A hostile or man-in-the-middle server can send an Authentication Switch Request for dialog over plain TCP, causing the driver to return the user's password in cleartext when sslMode=DISABLE and restrictedAuth=null, which is the default configuration. Properly verified TLS and local Unix sockets are not exposed to this transport vector. This issue is fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses mariadb-connector-j, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.39%, higher than 33% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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