{"id":"CVE-2026-53711","aliases":["EUVD-2026-98770","GHSA-x6gc-rm5j-55mw"],"status":"published","title":"MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UI","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.","severity":{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00363,"percentile":0.3038,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2026-10-13T14:34:01Z","modified":"2026-11-04T02:48:04Z","products":[{"vendor":"ibm","product":"mcp-context-forge"}],"references":[{"url":"https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-x6gc-rm5j-55mw","tags":["x_refsource_CONFIRM","exploit","advisory"]},{"url":"https://github.com/IBM/mcp-context-forge/pull/337","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/IBM/mcp-context-forge/commit/acd16196158f9a393187551b21a2fc61650f2e3d","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/IBM/mcp-context-forge/releases/tag/v0.3.1","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53711.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53711","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-53711","title":"MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UI","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.","status":"published","published":"2026-10-13T14:34:01.069Z","modified":"2026-10-13T15:48:27.245Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:20:00.11477Z"}],"euvd":[{"id":"EUVD-2026-98770","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.","status":"published","published":"2026-10-13T14:34:01Z","modified":"2026-10-13T15:48:27Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T17:27:20.397021Z"}],"nvd":[{"id":"CVE-2026-53711","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.","status":"published","published":"2026-10-13T15:17:45.03Z","modified":"2026-10-16T20:04:29.76Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:57.132005Z"}],"osv":[{"id":"CVE-2026-53711","title":"MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UI","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.","status":"published","published":"2026-10-13T14:34:01.069Z","modified":"2026-11-06T10:46:33.829771362Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-06T11:08:47.346964Z"}]}}
