๐Ÿ” CVE Alert

CVE-2026-55859

MEDIUM 5.9

MariaDB Connector/R2DBC: Inappropriate Encoding for Output Context and Improper Encoding or Escaping of Output in org.mariadb:r2dbc-mariadb

CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th

MariaDB Connector/R2DBC is a non-blocking MariaDB and MySQL client implemented in Java. Prior to 1.4.1, org.mariadb:r2dbc-mariadb encodes and decodes all character data under the assumption that the connection character set is UTF-8. A server can announce a mid-session change to character_set_client through the OK-packet session-state-tracking mechanism, including through SET NAMES executed by a stored routine or trigger, server configuration, or a hostile or man-in-the-middle server. If the new character set is not UTF-8, the driver continues to exchange UTF-8 while the server interprets the same bytes under a different 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 raises R2dbcNonTransientResourceException with SQLState 08000 and closes the connection. This issue is fixed in version 1.4.1.

CWE CWE-116 CWE-838
Vendor mariadb-corporation
Product mariadb-connector-r2dbc
Published Aug 28, 2026
Stay Ahead of the Next One

Get instant alerts for mariadb-corporation mariadb-connector-r2dbc

Be the first to know when new medium vulnerabilities affecting mariadb-corporation mariadb-connector-r2dbc are published โ€” delivered to Slack, Telegram or Discord.

Get Free Alerts โ†’ Free ยท No credit card ยท 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

Affected Versions

mariadb-corporation / mariadb-connector-r2dbc
< 1.4.1
org.mariadb / r2dbc-mariadb
< 1.4.1

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/mariadb-corporation/mariadb-connector-r2dbc/security/advisories/GHSA-5rqc-86vf-g8r2 github.com: https://github.com/mariadb-corporation/mariadb-connector-r2dbc/commit/38bad9afebc6c581a853656a42f9ebf403b1b1b7 github.com: https://github.com/mariadb-corporation/mariadb-connector-r2dbc/releases/tag/1.4.1 jira.mariadb.org: https://jira.mariadb.org/browse/R2DBC-124