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CVE-2026-11918 (GCVE-0-2026-11918)

Vulnerability from cvelistv5 – Published: 2026-09-15 17:28 – Updated: 2026-09-15 17:28
VLAI
Title
IBM ContextForge MCP Gateway is affected by security filter bypass via nested payload structures
Summary
IBM ContextForge MCP Gateway <= v1.0.4 IBM mcp-context-forge could allow an authenticated user to bypass protection mechanisms due to incomplete recursive inspection of nested payload content.
CWE
  • CWE-184 - Incomplete List of Disallowed Inputs
Assigner
References
URL Tags
https://www.ibm.com/support/pages/node/7285720 vendor-advisorypatch
Impacted products
Vendor Product Version CPE status
IBM ContextForge MCP Gateway Affected: <= v1.0.4
    cpe:2.3:a:ibm:contextforge_mcp_gateway:*:*:*:*:*:*:*:*
Create a notification for this product.
Show details on NVD website

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          ],
          "product": "ContextForge MCP Gateway",
          "vendor": "IBM",
          "versions": [
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          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.4,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
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              "description": "CWE-184 Incomplete List of Disallowed Inputs",
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      "providerMetadata": {
        "dateUpdated": "2026-09-15T17:28:57.954Z",
        "orgId": "9a959283-ebb5-44b6-b705-dcc2bbced522",
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              "value": "\u003cdiv\u003e\u003cbr/\u003e\u003cdiv\u003e| Product | Affected Version(s) | Fix Version | Instructions |\u003c/div\u003e\u003cdiv\u003e|---|---|---|---|\u003c/div\u003e\u003cdiv\u003e| | \u0026lt;=1.0.4 | 1.0.5 | Upgrade to v1.0.5 or later.\u00a0. |\u003c/div\u003e\u003c/div\u003e\u003cp\u003e\u003cstrong\u003eIBM strongly recommends addressing the vulnerability now.\u003c/strong\u003e\u003c/p\u003e\u003cdiv\u003e\u003ctable\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd\u003e\u003cstrong\u003eProduct(s)\u003c/strong\u003e\u003c/td\u003e\u003ctd\u003e\u003cstrong\u003eVersion(s) number and/or range\u00a0\u003c/strong\u003e\u003c/td\u003e\u003ctd\u003e\u003cstrong\u003eRemediation/Fix/Instructions\u003c/strong\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd\u003eIBM ContextForge MCP Gateway\u003c/td\u003e\u003ctd\u003e\u0026lt;=1.0.4\u003c/td\u003e\u003ctd\u003e\u003cp\u003ev1.0.5 or later\u003c/p\u003e\u003cp\u003eSee [release notes](\u003ca href=\"https://github.com/IBM/mcp-context-forge/releases/tag/v1.0.5%29\" rel=\"nofollow\"\u003ehttps://github.com/IBM/mcp-context-forge/releases/tag/v1.0.5)\u003c/a\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e\u003cp\u003e\u00a0Note: \u0026lt;Component A / B names\u0026gt; are bundled with \u0026lt;Product profile name\u0026gt; to provide \u0026lt;feature / function description\u0026gt;\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"
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          "value": "| Product | Affected Version(s) | Fix Version | Instructions |\n\n|---|---|---|---|\n\n| | \u003c=1.0.4 | 1.0.5 | Upgrade to v1.0.5 or later.\u00a0. |\n\n\n\n\n\nIBM strongly recommends addressing the vulnerability now.\n\nProduct(s)Version(s) number and/or range\u00a0Remediation/Fix/InstructionsIBM ContextForge MCP Gateway\u003c=1.0.4\n\nv1.0.5 or later\n\n\n\nSee [release notes]( https://github.com/IBM/mcp-context-forge/releases/tag/v1.0.5) https://github.com/IBM/mcp-context-forge/releases/tag/v1.0.5%29 \n\n\n\n\n\n\u00a0Note: \u003cComponent A / B names\u003e are bundled with \u003cProduct profile name\u003e to provide \u003cfeature / function description\u003e"
        }
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      "title": "IBM ContextForge MCP Gateway is affected by security filter bypass via nested payload structures",
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              "value": "\u003cdiv\u003e\u003cdiv\u003eThere is no workaround that fully prevents the bypass while keeping the affected plugins active. Operators may disable `regex_filter` and `deny_filter` in `plugins/config.yaml` to prevent exploitation, at the cost of losing the filtering controls those plugins provide.\u003c/div\u003e\u003cdiv\u003eIBM strongly recommends upgrading to v1.0.5 or higher, which replaces the top-level-only scan loops with a recursive walker in both plugins.\u003c/div\u003e\u003c/div\u003e"
            }
          ],
          "value": "There is no workaround that fully prevents the bypass while keeping the affected plugins active. Operators may disable `regex_filter` and `deny_filter` in `plugins/config.yaml` to prevent exploitation, at the cost of losing the filtering controls those plugins provide.\n\nIBM strongly recommends upgrading to v1.0.5 or higher, which replaces the top-level-only scan loops with a recursive walker in both plugins."
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9a959283-ebb5-44b6-b705-dcc2bbced522",
    "assignerShortName": "ibm",
    "cveId": "CVE-2026-11918",
    "datePublished": "2026-09-15T17:28:57.954Z",
    "dateReserved": "2026-06-10T17:00:06.831Z",
    "dateUpdated": "2026-09-15T17:28:57.954Z",
    "state": "PUBLISHED"
  },
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      "cve": "CVE-2026-11918",
      "date": "2026-09-16",
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  }
}



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