Medium · CVSS 5.1CVE-2026-53711

MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UICVE-2026-53711

Answer in brief

CVE-2026-53711 records a Medium severity (CVSS 5.1) vulnerability in MCP ContextForge: Global Prompts stored cross-site scripting compromises the Admin UI. The current sources do not mark it as known exploited. The current feed maps IBM/mcp-context-forge (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 13, 2026Updated Oct 13, 2026Source checked Oct 13, 2026First seen by HOL Oct 13, 2026Material review Oct 13, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 5.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps IBM/mcp-context-forge (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
IBM/mcp-context-forgegeneric	>=0.2.0 <0.3.1	0.3.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for IBM/mcp-context-forge.
Review the reported fix. Update IBM/mcp-context-forge to 0.3.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 13, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 13, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 13, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.