Flowise: Unauthenticated OAuth 2.0 Access Token Disclosure via Public Chatflow

published 2026-04-16 6 mo ago modified 2026-10-26 13 d ago also GHSA-6f7g-v4pp-r667 , EUVD-2026-25290

cvss: 8.2; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits: 0; none known

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.0, Flowise contains an authentication bypass vulnerability that allows an unauthenticated attacker to obtain OAuth 2.0 access tokens associated with a public chatflow. By accessing a public chatflow configuration endpoint, an attacker can retrieve internal workflow data, including OAuth credential identifiers, which can then be used to refresh and obtain valid OAuth 2.0 access tokens without authentication. This vulnerability is fixed in 3.1.0.

Patch / fix

fixed in 2

npm flowise 3.1.0
flowiseai flowise 3.1.0

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 6 mo ago (2026-04-24)

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-6f7g-v4pp-r667 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N
CNA	4.0	7.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
GitHub	3.1	8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	flowise	<3.1.0	3.1.0

Affected products

FlowiseAI Flowise

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality

References

github.com /FlowiseAI/Flowise/security/advisories/GHSA-6f7g-v4pp-r667
exploit, web, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2026-41273
advisory
github.com /FlowiseAI/Flowise
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary