CVE-2026-11918
IBM ContextForge MCP Gateway is affected by security filter bypass via nested payload structures
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.4
IBM ContextForge MCP Gateway is affected by security filter bypass via nested payload structures
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.
- Record
CVE-2026-11918- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-184
- Updated
- 2026-11-02
EUVDEUVD-2026-78898
5.4
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.
- Record
EUVD-2026-78898- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-x4xw-xv9j-3c3q
5.4
IBM ContextForge MCP Gateway <= v1.0.4 IBM mcp-context-forge could allow an authenticated user to...
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.
- Record
GHSA-x4xw-xv9j-3c3q- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-184
- Updated
- 2026-11-02
NVD
5.4
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.
- Record
CVE-2026-11918- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-184
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-11918 is a medium vulnerability (CVSS 5.4) in Ibm Contextforge Mcp Gateway, published September 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 19th percentile. No source names a fixed version.