CVE-2026-55418

FastGPT is an open source AI knowledge base platform. Prior to v4.15.0-beta5, two FastGPT file handlers authorize an unrelated resource and then sign or read an S3 object using a key taken directly from the request, without checking that the key belongs to the caller's team. Because S3 object keys are global within the bucket and carry the tenant id only as a path segment, an attacker can supply another team's key and obtain its file contents through the chat-file presign endpoint or dataset preview endpoint. This issue is fixed in version v4.15.0-beta5.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/labring/FastGPT/commit/decb6d2fb1417fb9e2bca145d2dcc9cbcf06396c
https://github.com/labring/FastGPT/pull/7104
https://github.com/labring/FastGPT/releases/tag/v4.15.0-beta5
https://github.com/labring/FastGPT/security/advisories/GHSA-6rxv-p43w-mmx5

Configurations

No configuration.

History

07 Jul 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-07 22:16

Updated : 2026-07-09 16:16

NVD link : CVE-2026-55418

Mitre link : CVE-2026-55418

CVE.ORG link : CVE-2026-55418

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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