gcdRadar
archive/Patch now/AIR-2026-1023
closedclosed 9 Apr 2026Patch now2 Disclosed vulnerabilityAI

Apollo MCP Server Host Header Validation Vulnerability

Apollo MCP Server

Apollo MCP Server fails to validate the Host header on incoming HTTP requests when using StreamableHTTP transport. This could allow malicious websites to issue requests to the local server via DNS rebinding techniques.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
8.1
EPSS
<0.01 · top 92% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
9 Apr 2026
last update
9 Apr 2026
CVE ids
CVE-2026-35577other records

Timeline · 1

  1. 9 Apr 2026CVE-2026-35577: Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools.

Sources · 1

Advisories and databases

  1. 2026-04-09
    CVE-2026-35577: Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools.
    NVD · nvd.nist.gov/vuln/detail/CVE-2026-35577

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerability
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Framework / tooling
owasp llm top 10
LLM03:2025 Supply Chain
mitre atlas
no technique for these categories
tags
dns-rebindingmcp
dates
happened 9 Apr 2026 · first reported 9 Apr 2026
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# Apollo MCP Server Host Header Validation Vulnerability

https://gcdradar.vercel.app/incidents/apollo-mcp-server-host-header-validation-vulnerability · AIR-2026-1023 · closed 2026-04-09

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-04-09
- AI role: Attack on AI
- Products: Apollo MCP Server
- CVE ids: CVE-2026-35577
- CVSS: 8.1

## Summary

Apollo MCP Server fails to validate the Host header on incoming HTTP requests when using StreamableHTTP transport. This could allow malicious websites to issue requests to the local server via DNS rebinding techniques.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-04-09: CVE-2026-35577: Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools. (https://nvd.nist.gov/vuln/detail/CVE-2026-35577)

## Sources

- 2026-04-09 NVD: CVE-2026-35577: Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools. https://nvd.nist.gov/vuln/detail/CVE-2026-35577

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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