What is CVE-2026-30821?

CVE-2026-30821 is a critical-severity vulnerability in Flowiseai Flowise, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-03-07.

How severe is CVE-2026-30821?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Arbitrary file upload in Flowiseai Flowise

CVE-2026-30821

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to version 3.0.13, the /api/v1/attachments/:chatflowId/:chatId endpoint is listed in WHITELIST_URLS, allowing unauthenticated access to the file…

Vulnerability class: Unrestricted File Upload

EPSS: 0.183 (96.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Flowiseai Flowise — versions < 3.0.13

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
security-advisories@github.com (Product, x_refsource_MISC, Release Notes)

Frequently asked questions

What is CVE-2026-30821?: CVE-2026-30821 is a critical-severity vulnerability in Flowiseai Flowise, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-03-07.
How severe is CVE-2026-30821?: Critical severity. CVSS v3 base score is 9.8 out of 10.