CVE-2026-55860

MariaDB Connector/R2DBC: Cleartext password disclosure to a man-in-the-middle server (clear-text auth plugins not gated on a secure transport)

Published Aug 28, 2026 CVSS 3.1 · 5.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-c857-9x2m-cvh2 org.mariadb:r2dbc-mariadb vulnerable to cleartext password disclosure to a man-in-the-middle server (clear-text auth plugins not gated on a secure transport)
History
Type Values Removed Values Added
First Time appeared Mariadb
Mariadb connector-r2dbc
Vendors & Products Mariadb
Mariadb connector-r2dbc
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title MariaDB Connector/R2DBC: Cleartext password disclosure to a man-in-the-middle server (clear-text auth plugins not gated on a secure transport)
Weaknesses CWE-319
CWE-522
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 31, 2026, 2:05 PM
Reserved
Jun 17, 2026, 4:44 PM
Status
Awaiting Analysis
Published
Aug 28, 2026, 11:17 PM
Modified
Sep 8, 2026, 9:08 PM