CVE-2026-41273Public exploitNetwork attack vector

OAuth token disclosure via unauthenticated refresh endpoint

Published Apr 23, 2026 · Updated Apr 23, 2026

Authentication bypass in Flowise before 3.1.0 allows remote attackers to obtain OAuth 2.0 access tokens through public chatflows. The public chatbot configuration endpoint returns flowData containing credential identifiers, and the OAuth refresh endpoint accepts those identifiers without authentication or authorization. Exploitation requires a self-hosted instance with a public chatflow linked to an OAuth credential and grants access to the associated third-party service.

CVSS severity7.7
High
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Flowise before 3.1.0 allows remote attackers to obtain OAuth 2.0 access tokens through public chatflows. The public chatbot configuration endpoint returns flowData containing credential identifiers, and the OAuth refresh endpoint accepts those identifiers without authentication or authorization. Exploitation requires a self-hosted instance with a public chatflow linked to an OAuth credential and grants access to the associated third-party service.

The record

CVE
CVE-2026-41273
Published
Apr 23, 2026
Updated
Apr 23, 2026
Vendor
FlowiseAI
Product
Flowise
Classifications
CWE-306, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FlowiseAI · Flowiseversion=< 3.1.0

Published CVSS scores

7.7GitHub Security AdvisoryCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1528Steal Application Access Token

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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