CVE-2026-55418
HIGH
MEDIUM
Priority: 0.04
BB Relevance:
77/100
Published: 2026-07-07
Modified: 2026-10-25
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
Conf. Impact
Scope Change
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Changed
C:
High
I:
None
A:
None
Description
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.