{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.7.14"
              },
              {
                "introduced": "3.0.0-alpha"
              },
              {
                "fixed": "3.3.5"
              },
              {
                "introduced": "3.4.0"
              },
              {
                "fixed": "3.4.3"
              },
              {
                "introduced": "3.5.0"
              },
              {
                "fixed": "3.5.9"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "introduced": "6f7aba384d47f97c4e4e98b19f677415c7084db7"
            },
            {
              "introduced": "c19f608838fdcb18fa81cab8a607afdaa5131a58"
            },
            {
              "introduced": "8be57f3b4bd0b1112cf871d9426beda6919b3bb7"
            },
            {
              "fixed": "defeee068496e3f6312e775c7de864f1b06388d4"
            },
            {
              "fixed": "f522a2f560c6e07d1d4b9a7957ed31bc57038af4"
            },
            {
              "fixed": "606bb6d6cf8fc02dc723ec468b5f753680da0993"
            },
            {
              "fixed": "df4ebe2c61293b7a79ab9dd440199544305d1f38"
            },
            {
              "fixed": "300716bef1e1d0370a41be7863b88aa2d55fbb69"
            },
            {
              "fixed": "7b3c69221b5463ee03472654040b3f6b9e5329c7"
            },
            {
              "fixed": "8cfd9df697372ad4ed09fe87a34b34babb6d43d6"
            },
            {
              "fixed": "c555c9b477521be0c35c3a5461f9f46681553607"
            }
          ],
          "repo": "https://github.com/mariadb-corporation/mariadb-connector-j",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-xvr9-35cr-46v9"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-838"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55858.json"
  },
  "details": "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.",
  "id": "CVE-2026-55858",
  "modified": "2026-08-30T03:30:44.868684790Z",
  "published": "2026-08-28T22:46:40.114Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/2.7.14"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.3.5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.4.3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/releases/tag/3.5.9"
    },
    {
      "type": "WEB",
      "url": "https://jira.mariadb.org/browse/CONJ-1317"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55858.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/security/advisories/GHSA-xvr9-35cr-46v9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55858"
    },
    {
      "type": "FIX",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/commit/300716bef1e1d0370a41be7863b88aa2d55fbb69"
    },
    {
      "type": "FIX",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/commit/7b3c69221b5463ee03472654040b3f6b9e5329c7"
    },
    {
      "type": "FIX",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/commit/8cfd9df697372ad4ed09fe87a34b34babb6d43d6"
    },
    {
      "type": "FIX",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-j/commit/c555c9b477521be0c35c3a5461f9f46681553607"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "MariaDB Connector/J: Inappropriate Encoding for Output Context in org.mariadb.jdbc:mariadb-java-client"
}