Vulnerability Description
MariaDB Connector/R2DBC is a non-blocking MariaDB and MySQL client implemented in Java. Prior to 1.4.1, org.mariadb:r2dbc-mariadb does not gate clear-text password authentication plugins on transport encryption because the AuthenticationPlugin interface has no capability for a plugin to require a secure connection. A hostile or man-in-the-middle MariaDB server can send an AuthSwitchRequest naming mysql_clear_password or dialog (PAM) over a plain-TCP unencrypted connection, and AuthenticationFlow permits ClearPasswordPluginFlow or PamPluginFlow to return the user's password as cleartext bytes on the wire. The disclosed credentials can subsequently be used to authenticate directly to the database server. This issue is fixed in version 1.4.1.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/mariadb-corporation/mariadb-connector-r2dbc/commit/be786603ec
- https://github.com/mariadb-corporation/mariadb-connector-r2dbc/releases/tag/1.4.
- https://github.com/mariadb-corporation/mariadb-connector-r2dbc/security/advisori
- https://hackerone.com/reports/3784556
- https://jira.mariadb.org/browse/R2DBC-115
FAQ
What is CVE-2026-55860?
CVE-2026-55860 is a vulnerability with a CVSS score of 5.9 (MEDIUM). MariaDB Connector/R2DBC is a non-blocking MariaDB and MySQL client implemented in Java. Prior to 1.4.1, org.mariadb:r2dbc-mariadb does not gate clear-text password authentication plugins on transport ...
How severe is CVE-2026-55860?
CVE-2026-55860 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55860?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.