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Full vulnerability report · 2025
CVE-2025-59434High confidence

Critical Multi-Tenant Variable Disclosure in Flowise Cloud via Custom JavaScript Function

FlowiseAI · Flowise

Official source article: GitHub GHSA-435C-MG9P-FV22 ↗. Check the applicable product and release in the original source.

9.6CriticalCVSS 3.1
Recommended action
Within 72 hours

Critical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.

Fix not verified
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • EPSS is 3.40% for the current model date.

Compensating controls

  • Restrict the affected network interface to trusted sources where business-safe.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs FlowiseAI Flowise and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2025-30835

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 72 hours

Critical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.

Fix not verified
01

What, why and how

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to August 2025 Cloud-Hosted Flowise, an authenticated vulnerability in Flowise Cloud allows any user on the free tier to access sensitive environment variables from other tenants via the Custom JavaScript Function node. This includes secrets such as OpenAI API keys, AWS credentials, Supabase tokens, and Google Cloud secrets — resulting in a full cross-tenant data exposure. This issue has been patched in the August 2025 Cloud-Hosted Flowise.

What

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to August 2025 Cloud-Hosted Flowise, an authenticated vulnerability in Flowise Cloud allows any user on the free tier to access sensitive environment variables from other tenants via the Custom JavaScript Function node. This includes secrets such as OpenAI API keys, AWS credentials, Supabase tokens, and Google Cloud secrets — resulting in a full cross-tenant data exposure. This issue has been patched in the August 2025 Cloud-Hosted Flowise.

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to August 2025 Cloud-Hosted Flowise, an authenticated vulnerability in Flowise Cloud allows any user on the free tier to access sensitive environment variables from other tenants via the Custom JavaScript Function node. This includes secrets such as OpenAI API keys, AWS credentials, Supabase tokens, and Google Cloud secrets — resulting in a full cross-tenant data exposure. This issue has been patched in the August 2025 Cloud-Hosted Flowise.

Why

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

CISA Vulnrichment records proof-of-concept exploitation in its SSVC data. BlackTree has not independently executed or validated exploit material.

Likely attack path
a network path → Exposure of Sensitive Information to an Unauthorized Actor → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-200 ↗

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
NetworkCWE-200Public exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2025-2105Flowise: Mehrere Schwachstellen

Ein entfernter, authentisierter oder anonymer Angreifer kann mehrere Schwachstellen in Flowise ausnutzen, um Informationen offenzulegen und beliebigen Code auszuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20250924Security Bulletin 24 Sep 2025

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 24 Sep 2025, published on 24 September 2025. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix not verified
Affected
Flowise: < cloud-hosted (as of Aug 2025)
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 22 Sept 2025 · Last source change 22 Sept 2025, 19:47 UTC · CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2025-30835
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    < cloud-hosted (as of Aug 2025) · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    Flowise: < cloud-hosted (as of Aug 2025) · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
ENISA EUVD · EUVD-2025-30835↗CISA Vulnrichment SSVC evidence↗CVE authority or vendor reference · GitHub GHSA-435C-MG9P-FV22↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2025-59434 · cve.blacktree.nl