CVE-2026-53711: medium-severity vulnerability in IBM mcp-context-forge
MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UI
Published
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.1epss 0.4%
exploitation probability
0.4%top 70% of all CVEs
observed exploitation
nono source reports it
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/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Affected products
IBM · mcp-context-forgeRelated CVEs — IBM mcp-context-forge
In the same product, most dangerous first.
CVE-2026-53710CRITICALMCP Context Forge: RestrictedPython sandbox bypass via getattr builtin in python_sandbox_serverEPSS 1.1%CVE-2026-53709CRITICALMCP Context Forge: Hardcoded default JWT_SECRET_KEY shipped in source and .env.example enables pre-authentication platform admin token forgeryEPSS 0.6%CVE-2026-53708MEDIUMContextForge: DNS TOCTOU race condition causes SSRF protection bypass (`/admin/gateways/test`)EPSS 0.4%