Authenticated filter bypass via nested payload evasion
Published Sep 15, 2026 · Updated Sep 15, 2026
Protection bypass in IBM ContextForge MCP Gateway 1.0.4 and earlier allows remote authenticated users to evade content filtering. The gateway's payload security filter incompletely traverses nested content, allowing prohibited material deeper in a structured request to escape inspection. A valid authenticated session and crafted nested payload are required; the published information specifies no consequence beyond bypass of the intended protection.
Summary
What happened
Protection bypass in IBM ContextForge MCP Gateway 1.0.4 and earlier allows remote authenticated users to evade content filtering. The gateway's payload security filter incompletely traverses nested content, allowing prohibited material deeper in a structured request to escape inspection. A valid authenticated session and crafted nested payload are required; the published information specifies no consequence beyond bypass of the intended protection.
The record
- CVE
- CVE-2026-11918
- Published
- Sep 15, 2026
- Updated
- Sep 15, 2026
- Vendor
- IBM
- Product
- ContextForge MCP Gateway
- Classifications
- T1687
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 15, 2026CVE publishedPublication date reported by the CVE source.
- Sep 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=<= v1.0.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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