CVE-2026-554188.6HighCWE-639

CVE-2026-55418: FastGPT: S3 presign/read handlers do not bind the object key to the caller's team (cross-team file disclosure)

labring · FastGPT

Affected: labring FastGPT · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.5%probability of exploitation in the next 30 days

42nd percentile

050100

Higher than 42% of scored CVEs

8.6HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

labring · FastGPT< 4.15.0-beta5

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Insecure Direct Object Reference
Vendor: labring
Published: July 2026
Band: Unlikely (under 1%), July 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-55418 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.