CVE-2026-61643

Deferred Deferred - Pending Action

Authenticated Workflow Node Access to Private HTTP Toolset in FastGPT

Publication date: 2026-07-15

Last updated on: 2026-07-20

Assigner: GitHub, Inc.

Description

FastGPT is a knowledge-based AI application platform. From 4.14.17 until 4.15.0-beta5, an authenticated FastGPT user can save a workflow node that points to another user's private HTTP toolset by using a crafted saved tool id such as http-<victim_toolset_app_id>/<tool_name>. The normal toolset routes deny access, but the workflow save and runtime path did not apply the same authorization check to the referenced toolset, allowing /api/v2/chat/completions to resolve the saved reference and execute the victim-owned HTTP tool. This issue is fixed in version 4.15.0-beta5.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-07-15

Last Modified

2026-07-20

Generated

2026-08-05

AI Q&A

2026-07-15

EPSS Evaluated

2026-08-03

NVD

CVE-2026-61643

EUVD

EUVD-2026-44753

Affected Vendors & Products

Vendor	Product	Version / Range
fastgpt	fastgpt	From 4.14.17 (inc) to 4.15.0-beta5 (inc)
labring	fastgpt	4.14.17
labring	fastgpt	4.14.23
labring	fastgpt	4.15.0-beta3
labring	fastgpt	From 4.14.17 (inc) to 4.15.0-beta5 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-863	The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

Attack-Flow Graph

Executive Summary

This vulnerability in FastGPT allows an authenticated user to save a workflow node that references another user's private HTTP toolset using a manipulated tool ID. The system fails to validate ownership during workflow execution, bypassing normal access controls. This enables the attacker to execute the victim's private toolset through the chat runtime.

Detection Guidance

Check FastGPT logs for unauthorized workflow executions or toolset references. Look for workflow nodes with tool IDs like http-<victim_toolset_app_id>/<tool_name>. Review saved workflows for suspicious toolset references pointing to other users' private resources.

Impact Analysis

An attacker could access or manipulate another user's private toolset output, potentially leading to unauthorized data exposure or service interactions. In local environments, synthetic credentials might be used to interact with external mock services, increasing the risk of data leakage or service misuse.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating confidentiality requirements in GDPR and HIPAA. Compliance may be impacted due to potential data breaches, unauthorized processing, or exposure of protected health information or personal data.

Mitigation Strategies

Upgrade FastGPT to version 4.15.0-beta5 or later. Review and remove any workflows created between versions 4.14.17 and 4.15.0-beta5 that reference external toolsets. Audit user permissions and toolset access controls.

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