CVE-2026-119281: MariaDB Connector/J: Server could switch character_set_results away from UTF-8 without the client noticing

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-29 · updated 2026-10-30
Weakness: CWE-838

Description

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 3.5.11, the connector assumed result bytes were UTF-8 but guarded only changes to character_set_client. It did not reject non-UTF-8 character_set_results changes and relied on the server's global session_track_system_variables configuration to report character-set changes. A malicious or compromised server, or a machine-in-the-middle attacker, could suppress tracking or change the result charset so application strings differed from the returned bytes, potentially defeating application-side validation or escaping that depended on the decoded values. This issue is fixed in versions 3.3.7, 3.4.5, and 3.5.11.

Affected products

mariadb-corporation mariadb-connector-j: from 3.0.0, < 3.3.7; from 3.4.0, < 3.4.5; from 3.5.0, < 3.5.11

References

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