FKIE_CVE-2026-55859

Vulnerability from fkie_nvd - Published: 2026-08-28 23:17 - Updated: 2026-09-08 21:08
Severity
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Summary
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.
References
security-advisories@github.comhttps://github.com/mariadb-corporation/mariadb-connector-r2dbc/commit/38bad9afebc6c581a853656a42f9ebf403b1b1b7
security-advisories@github.comhttps://github.com/mariadb-corporation/mariadb-connector-r2dbc/releases/tag/1.4.1
security-advisories@github.comhttps://github.com/mariadb-corporation/mariadb-connector-r2dbc/security/advisories/GHSA-5rqc-86vf-g8r2
security-advisories@github.comhttps://jira.mariadb.org/browse/R2DBC-124
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "mariadb-connector-r2dbc",
          "vendor": "mariadb-corporation",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.4.1"
            }
          ]
        },
        {
          "product": "r2dbc-mariadb",
          "vendor": "org.mariadb",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.4.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-55859",
  "lastModified": "2026-09-08T21:08:37.320",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-55859",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-31T15:21:03.102797Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-28T23:17:09.007",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-r2dbc/commit/38bad9afebc6c581a853656a42f9ebf403b1b1b7"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-r2dbc/releases/tag/1.4.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mariadb-corporation/mariadb-connector-r2dbc/security/advisories/GHSA-5rqc-86vf-g8r2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://jira.mariadb.org/browse/R2DBC-124"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-116"
        },
        {
          "lang": "en",
          "value": "CWE-838"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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