Vulnerability details
CVE-2026-55418
labring FastGPT
FastGPT: S3 presign/read handlers do not bind the object key to the caller's team (cross-team file disclosure)
CVSS 3.1
8.6High
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.6High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| labring | FastGPT | < 4.15.0-beta5 | CVEProject cvelistV5 (CNA) |
References and advisories
4- https://github.com/labring/FastGPT/security/advisories/GHSA-6rxv-p43w-mmx5 x_refsource_CONFIRM
- https://github.com/labring/FastGPT/pull/7104 x_refsource_MISC
- https://github.com/labring/FastGPT/commit/decb6d2fb1417fb9e2bca145d2dcc9cbcf06396c x_refsource_MISC
- https://github.com/labring/FastGPT/releases/tag/v4.15.0-beta5 x_refsource_MISC
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Details
- Published
- 2026-07-08
- Last updated
- 2026-07-09
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
0.48%
Probability of exploitation in 30 days
41.8%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- None
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-639Authorization Bypass Through User-Controlled Key