{"api_version":"1","generated_at":"2026-08-29T03:55:38+00:00","cve":"CVE-2026-55859","urls":{"html":"https://cve.report/CVE-2026-55859","api":"https://cve.report/api/cve/CVE-2026-55859.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55859","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55859"},"summary":{"title":"MariaDB Connector/R2DBC: Inappropriate Encoding for Output Context and Improper Encoding or Escaping of Output in org.mariadb:r2dbc-mariadb","description":"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. 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