Vulnerability-Lookup

GHSA-76G7-M3XW-X9GR

Vulnerability from github – Published: 2026-06-13 12:31 – Updated: 2026-06-13 12:31

Details

The Model Context Protocol has a security warning advising servers to validate the "Origin" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin's host. In v0.25.0, a new "--allowed-hosts" flag was introduced alongside the existing "--allowed-origins" flag, enabling users to specify permitted hosts at server startup. Both flags default to "", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to "", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations.

Severity

9.4 (Critical)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-11624"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-346"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-13T10:16:17Z",
    "severity": "CRITICAL"
  },
  "details": "The Model Context Protocol has a security warning advising servers to validate the \"Origin\" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin\u0027s host. In v0.25.0, a new \"--allowed-hosts\" flag was introduced alongside the existing \"--allowed-origins\" flag, enabling users to specify permitted hosts at server startup. Both flags default to \"*\", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to \"*\", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations.",
  "id": "GHSA-76g7-m3xw-x9gr",
  "modified": "2026-06-13T12:31:25Z",
  "published": "2026-06-13T12:31:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-11624"
    },
    {
      "type": "WEB",
      "url": "https://github.com/googleapis/mcp-toolbox/issues/3113"
    },
    {
      "type": "WEB",
      "url": "https://github.com/googleapis/mcp-toolbox/pull/2254"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-11624 (GCVE-0-2026-11624)

Vulnerability from cvelistv5 – Published: 2026-06-13 08:38 – Updated: 2026-06-13 08:38

Summary

The Model Context Protocol has a security warning advising servers to validate the "Origin" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin's host. In v0.25.0, a new "--allowed-hosts" flag was introduced alongside the existing "--allowed-origins" flag, enabling users to specify permitted hosts at server startup. Both flags default to "*", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to "*", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations.

Severity

9.4 (Critical)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CWE

CWE-346 - Origin Validation Error

Assigner

Google

References

2 references

URL	Tags
https://github.com/googleapis/mcp-toolbox/issues/3113
https://github.com/googleapis/mcp-toolbox/pull/2254

Impacted products

1 product

Vendor	Product	Version
Google	MCP Toolbox for Databases	Affected: 0 , < 0.25.0 (semver)

Credits

Jonathan Leitschuh (https://github.com/JLLeitschuh)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "MCP Toolbox for Databases",
          "vendor": "Google",
          "versions": [
            {
              "lessThan": "0.25.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Jonathan Leitschuh (https://github.com/JLLeitschuh)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "The Model Context Protocol has a security warning advising servers to validate the \"Origin\" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin\u0027s host. In v0.25.0, a new \"--allowed-hosts\" flag was introduced alongside the existing \"--allowed-origins\" flag, enabling users to specify permitted hosts at server startup. Both flags default to \"*\", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to \"*\", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations."
            }
          ],
          "value": "The Model Context Protocol has a security warning advising servers to validate the \"Origin\" header on all incoming connections to prevent DNS rebinding attacks. Prior to the v0.25.0 release, users had no way to validate the origin\u0027s host. In v0.25.0, a new \"--allowed-hosts\" flag was introduced alongside the existing \"--allowed-origins\" flag, enabling users to specify permitted hosts at server startup. Both flags default to \"*\", allowing users to implement strict access controls as needed without breaking existing setups. If either flag is set to \"*\", the server will output a startup warning about potential vulnerabilities. Documentation has also been updated to highlight these security considerations."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-275",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-275: DNS Rebinding"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.4,
            "baseSeverity": "CRITICAL",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-346",
              "description": "CWE-346: Origin Validation Error",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-13T08:38:42.908Z",
        "orgId": "14ed7db2-1595-443d-9d34-6215bf890778",
        "shortName": "Google"
      },
      "references": [
        {
          "url": "https://github.com/googleapis/mcp-toolbox/issues/3113"
        },
        {
          "url": "https://github.com/googleapis/mcp-toolbox/pull/2254"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "x_generator": {
        "engine": "Vulnogram 1.0.2"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "14ed7db2-1595-443d-9d34-6215bf890778",
    "assignerShortName": "Google",
    "cveId": "CVE-2026-11624",
    "datePublished": "2026-06-13T08:38:42.908Z",
    "dateReserved": "2026-06-08T20:57:51.543Z",
    "dateUpdated": "2026-06-13T08:38:42.908Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-76G7-M3XW-X9GR

CVE-2026-11624 (GCVE-0-2026-11624)

Tags

Sightings

Nomenclature