Vulnerability · Published Aug 28, 2026 · Assigned by GitHub_M
CVE-2026-55858MariaDB Connector/J: Inappropriate Encoding for Output Context in org.mariadb.jdbc:mariadb-java-client
Medium 5.9
In plain English
A medium-severity security flaw in mariadb-connector-j from mariadb-corporation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 59% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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, the connector encodes and decodes protocol text and performs client-side escaping under the assumption that the connection character set is UTF-8. The server can report a mid-session change to character_set_client through OK-packet session-state tracking, including a change caused by SET NAMES, a stored routine or trigger, server configuration, or a hostile server. If character_set_client changes to a non-UTF-8 value, the driver continues to read and write UTF-8 while the server interprets the same bytes under another 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 causes SQLException with SQLState 08000 and closes the connection. This issue is fixed in versions 2.7.14, 3.3.5, 3.4.3, and 3.5.9.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | org.mariadb.jdbc:mariadb-java-client | 2.7.14 | GHSA-xvr9-35cr-46v9 |
| Maven | org.mariadb.jdbc:mariadb-java-client | 3.3.5 | GHSA-xvr9-35cr-46v9 |
| Maven | org.mariadb.jdbc:mariadb-java-client | 3.4.3 | GHSA-xvr9-35cr-46v9 |
| Maven | org.mariadb.jdbc:mariadb-java-client | 3.5.9 | GHSA-xvr9-35cr-46v9 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| mariadb-corporation | mariadb-connector-j | < 2.7.14>= 3.0.0-alpha, < 3.3.5>= 3.4.0, < 3.4.3>= 3.5.0, < 3.5.9 |
Weakness: CWE-838 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
References
- https://github.com/mariadb-corporation/mariadb-connector-j/security/advisories/GHSA-xvr9-35cr-46v9 x_refsource_CONFIRM
- https://github.com/mariadb-corporation/mariadb-connector-j/commit/300716bef1e1d0370a41be7863b88aa2d55fbb69 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/commit/7b3c69221b5463ee03472654040b3f6b9e5329c7 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/commit/8cfd9df697372ad4ed09fe87a34b34babb6d43d6 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/commit/c555c9b477521be0c35c3a5461f9f46681553607 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/2.7.14 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.3.5 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.4.3 x_refsource_MISC
- https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.5.9 x_refsource_MISC
- https://jira.mariadb.org/browse/CONJ-1317 x_refsource_MISC