CVE-2026-53711
An authenticated attacker can save markup containing script-capable event handlers, and the code executes when another user views the saved prompt.
Does this matter?
Lower severity and a low EPSS score (0.36%). Track it; it rarely justifies an emergency change on its own.
Description
MCP Context Forge provides an MCP Admin UI for managing gateway resources. From 0.2.0 until 0.3.1, the Global Prompts feature stores a prompt template without sufficient output encoding before the MCP Admin UI renders it. An authenticated attacker can save markup containing script-capable event handlers, and the code executes when another user views the saved prompt. The stored cross-site scripting can alter the interface, present phishing content, observe keystrokes available to the page, and act with the viewer's browser session. This issue is fixed in version 0.3.1.
- CVSS 4.0
- 5.1 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.36% probability · 30th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- security-advisories@github.com
EPSS moved from 0.4% on 14 October 2026 to 0.4% on 26 October 2026.
References
- https://github.com/IBM/mcp-context-forge/commit/acd16196158f9a393187551b21a2fc61650f2e3d
- https://github.com/IBM/mcp-context-forge/pull/337
- https://github.com/IBM/mcp-context-forge/releases/tag/v0.3.1
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-x6gc-rm5j-55mw
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-x6gc-rm5j-55mw
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.