CVE-2026-11918 (GCVE-0-2026-11918)
Vulnerability from cvelistv5 – Published: 2026-09-15 17:28 – Updated: 2026-09-15 17:28
VLAI
EPSS
VEX
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.
Severity
5.4 (Medium)
CWE
- CWE-184 - Incomplete List of Disallowed Inputs
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://www.ibm.com/support/pages/node/7285720 | vendor-advisorypatch |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| IBM | ContextForge MCP Gateway |
Affected:
<= v1.0.4
cpe:2.3:a:ibm:contextforge_mcp_gateway:*:*:*:*:*:*:*:* |
{
"containers": {
"cna": {
"affected": [
{
"cpes": [
"cpe:2.3:a:ibm:contextforge_mcp_gateway:*:*:*:*:*:*:*:*"
],
"product": "ContextForge MCP Gateway",
"vendor": "IBM",
"versions": [
{
"status": "affected",
"version": "\u003c= v1.0.4"
}
]
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cp\u003eIBM ContextForge MCP Gateway \u0026lt;= 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.\u003c/p\u003e"
}
],
"value": "IBM ContextForge MCP Gateway \u003c= 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."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 5.4,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-184",
"description": "CWE-184 Incomplete List of Disallowed Inputs",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-15T17:28:57.954Z",
"orgId": "9a959283-ebb5-44b6-b705-dcc2bbced522",
"shortName": "ibm"
},
"references": [
{
"tags": [
"vendor-advisory",
"patch"
],
"url": "https://www.ibm.com/support/pages/node/7285720"
}
],
"solutions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"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"
}
],
"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"
}
],
"title": "IBM ContextForge MCP Gateway is affected by security filter bypass via nested payload structures",
"workarounds": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"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"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-11918",
"date": "2026-09-16",
"epss": "0.00272",
"percentile": "0.19691"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-11918\",\"sourceIdentifier\":\"psirt@us.ibm.com\",\"published\":\"2026-09-15T18:17:12.677\",\"lastModified\":\"2026-09-16T19:22:22.797\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"IBM ContextForge MCP Gateway \u003c= 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.\"}],\"affected\":[{\"source\":\"psirt@us.ibm.com\",\"affectedData\":[{\"vendor\":\"IBM\",\"product\":\"ContextForge MCP Gateway\",\"cpes\":[\"cpe:2.3:a:ibm:contextforge_mcp_gateway:*:*:*:*:*:*:*:*\"],\"versions\":[{\"version\":\"\u003c= v1.0.4\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"psirt@us.ibm.com\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N\",\"baseScore\":5.4,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.8,\"impactScore\":2.5}]},\"weaknesses\":[{\"source\":\"psirt@us.ibm.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-184\"}]}],\"references\":[{\"url\":\"https://www.ibm.com/support/pages/node/7285720\",\"source\":\"psirt@us.ibm.com\"}]}}"
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…