@bytebase/dbhub's read-only mode does not prevent database writes

{
  "id": "581ea4a144900f4ae506abe2317c354acb504a9bdab9a174c990175b22eea59d",
  "url": "https://osv.dev/vulnerability/CVE-2026-61788",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "@bytebase/dbhub's read-only mode does not prevent database writes",
    "summary": "DBHub is a database MCP server for Postgres, MySQL, SQL Server, Oracle, MariaDB, SQLite. Prior to version 0.22.6, setting `readonly = true` on the `execute_sql` tool does not make the connection read-only. The connectors are written to set PostgreSQL `default_transaction_read_only=on` (and open SQLite in `readOnly` mode), but that code is gated on a config value that is never populated, so it never runs. The only thing left enforcing read-only is a classifier that inspects the first keyword of each statement. Any `SELECT` that writes or has side effects through a function call passes it. With an ordinary role this allows sequence tampering; with a privileged role it allows writing arbitrary files on the server (`lo_export`), reading arbitrary host files (`pg_read_file`), and remote code execution (`dblink` + `COPY ... TO PROGRAM`). The HTTP transport is unauthenticated and binds to `0.0.0.0` by default, so this is reachable by any network caller of `/mcp`. Version 0.22.6 patches the issue.",
    "evidence": "osv:CVE-2026-61788",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-61788",
      "aliases": [
        "CVE-2026-61788",
        "GHSA-mwwr-p57h-56pf"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/bytebase/dbhub",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6647caa4bfc6c197731d88ee0ebd7baeb846d1c0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.22.6"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.22.6"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-61788.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:36.943849224Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/61xxx/CVE-2026-61788.json",
        "https://github.com/bytebase/dbhub/security/advisories/GHSA-mwwr-p57h-56pf",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-61788"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-184",
          "CWE-636",
          "CWE-863"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/61xxx/CVE-2026-61788.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-61788",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504284,
  "published_at": "2026-09-24T17:37:40.409+00:00"
}