CVE-2026-64870

Deferred Deferred - Pending Action

MaxKB Remote URL Access via Unsafe Requests

Publication date: 2026-07-30

Last updated on: 2026-07-30

Assigner: GitHub, Inc.

Description

MaxKB is an open-source AI assistant for enterprise. In versions 2.0.0 through 2.10.4-lts, UpdateStoreTool.update_tool passes caller-supplied download_url and download_callback_url values to requests.get without equivalent trusted-host and redirect validation, allowing an authenticated workspace user to make the server request internal, loopback, link-local, or cloud metadata URLs. A fix is present on the v2 branch but has not yet been included in a published release.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-07-30

Last Modified

2026-07-30

Generated

2026-07-31

AI Q&A

2026-07-31

EPSS Evaluated

N/A

NVD

CVE-2026-64870

EUVD

EUVD-2026-51201

Affected Vendors & Products

Vendor	Product	Version / Range
maxkb	maxkb	From 2.0.0 (inc) to 2.10.4-lts (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-918	The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

Executive Summary

MaxKB versions 2.0.0 through 2.10.4-lts have a vulnerability in UpdateStoreTool.update_tool where it passes user-supplied download_url and download_callback_url to requests.get without proper validation. This allows authenticated users to make the server request to internal, loopback, link-local, or cloud metadata URLs.

Detection Guidance

Check MaxKB server logs for unusual outbound requests to internal, loopback, or metadata URLs. Monitor network traffic for unexpected connections to cloud provider metadata endpoints (e.g., AWS IMDS, Azure Instance Metadata Service).

Commands: Use curl to test if the server follows redirects to untrusted hosts: curl -v -L http://your-maxkb-server/tools/update?download_url=http://internal-server. Example: curl -v http://localhost:8080/tools/update?download_url=http://169.254.169.254/latest/meta-data/

Impact Analysis

An attacker with access to a workspace could exploit this to make the server send requests to internal systems, potentially accessing sensitive data or services. This could lead to unauthorized information disclosure or further attacks on internal infrastructure.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating confidentiality requirements in GDPR and HIPAA. Organizations using affected versions may face compliance violations and potential legal consequences.

Mitigation Strategies

Upgrade to the latest patched version if available. If not, apply the v2 branch fix manually. Restrict network access to prevent outbound requests to internal or metadata URLs. Disable the UpdateStoreTool functionality if unused.

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