CVE-2026-35577

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Source

https://cve.org/CVERecord?id=CVE-2026-35577

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-35577.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-35577

Aliases

GHSA-wqrj-vp8w-f8vh

Published

2026-04-09T19:40:25.604Z

Modified

2026-07-15T01:48:52.983700019Z

Severity

6.8 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N CVSS Calculator

Summary

Missing Host Header Validation in Apollo MCP Server for Localhost Deployments

Details

Apollo MCP Server is a Model Context Protocol server that exposes GraphQL operations as MCP tools. Prior to version 1.7.0, the Apollo MCP Server did not validate the Host header on incoming HTTP requests when using StreamableHTTP transport. In configurations where an HTTP-based MCP server is run on localhost without additional authentication or network-level controls, this could potentially allow a malicious website—visited by a user running the server locally—to use DNS rebinding techniques to bypass same-origin policy restrictions and issue requests to the local MCP server. If successfully exploited, this could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the local user. This issue is limited to HTTP-based transport modes (StreamableHTTP). It does not affect servers using stdio transport. The practical risk is further reduced in deployments that use authentication, network-level access controls, or are not bound to localhost. This vulnerability is fixed in 1.7.0.

Database specific

{
    "cwe_ids": [
        "CWE-346"
    ],
    "cna_assigner": "GitHub_M",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35577.json"
}

References

Affected packages

Git / github.com/apollographql/apollo-mcp-server

Affected ranges

Type

GIT

Repo

https://github.com/apollographql/apollo-mcp-server

Events

Introduced

Fixed

3d1f5c9f18d32446212018f2fbd806b482a22705

Database specific

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.7.0"
        }
    ],
    "cpe": "cpe:2.3:a:apollographql:apollo_mcp_server:*:*:*:*:*:*:*:*",
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ]
}

Affected versions

v0.*

v0.1.0

v0.2.0

v0.2.1

v0.3.0

v0.4.0

v0.4.1

v0.4.2

v0.5.0

v0.5.1

v0.5.2

v0.6.0

v0.6.1

v0.7.0

v0.7.1

v0.7.2

v0.7.3

v0.7.4

v0.7.5

v0.8.0

v0.9.0

v1.*

v1.0.0

v1.1.0

v1.1.1

v1.2.0

v1.2.1

v1.3.0

v1.4.0

v1.4.1

v1.5.0

v1.6.0

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-35577.json"