Cross-Site Scripting in MCP Context Forge Admin UI by IBM
CVE-2026-53711

5.1MEDIUM

Key Information:

Vendor

IBM
Status
Mcp-context-forge
Vendor
CVE Published:
13 October 2026

What is CVE-2026-53711?

MCP Context Forge, an administration tool by IBM for managing gateway resources, is vulnerable to stored cross-site scripting (XSS). This vulnerability arises from the Global Prompts feature, which inadequately encodes output when rendering user-saved prompt templates in the MCP Admin UI. An authenticated attacker can insert malicious script-capable event handlers into the prompt. When another user views the saved prompt, the injected script executes, potentially altering the UI and enabling phishing attacks, keystroke logging, or unauthorized actions within the compromised browser session. The issue was addressed in version 0.3.1, rendering the affected versions no longer susceptible to exploitation.

Affected Version(s)

mcp-context-forge >= 0.2.0, < 0.3.1

References

https://github.com/IBM/mcp-context-forge/security/advisor...
x_refsource_CONFIRM
https://github.com/IBM/mcp-context-forge/pull/337
x_refsource_MISC
https://github.com/IBM/mcp-context-forge/commit/acd161961...
x_refsource_MISC

CVSS V4

Score:
5.1
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.