CVE-2026-41266 — flowise
CVE-2026-41266 is a Information Exposure vulnerability in flowise. A fix is available for flowise — see the affected versions and patch details below.
Flowise: Sensitive Data Leak in public-chatbotConfig
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.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41266.
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.
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
/api/v1/public-chatbotConfig/:id ep exposes sensitive data including API keys, HTTP authorization headers and internal configuration without any authentication. An attacker with knowledge just of a chatflow UUID can retrieve credentials stored in password type fields and HTTP headers, leading to credential theft and more.
Details
Knowledge of chatflow UUID can be obtained from embedded chat widgets, referrer headers or logs and it's the only prerequest.
getSinglePublicChatbotConfig function in packages/server/src/services/chatflows/index.ts returns the full flowData object without authorization check or data sanitization.
There is a comment as "Safe as public endpoint as chatbotConfig doesn't contain sensitive credential" but flowData does contain sensitive data such as:
type: 'password' fields are stored in plaintext (unstructuredAPIKey in S3File node).
HTTP Authorization headers in POST / GET Requests nodes.
Internal API endpoints and webhook URLs.
PoC
- Add an S3 File node, set "File Processing Method" to "Unstructured".
- Enter an API key in "Unstructured API KEY" field or add a Requests Post node with Authorization header.
- Save the chatflow.
curl -s "https://localhost/api/v1/public-chatbotConfig/{CHATFLOW_UUID}"
Response:
{
"flowData": "{...\"unstructuredAPIKey\":\"victim_key\"...\"requestsPostHeaders\":\"Bearer victim_token\"...}"
}
Impact
Impacts all Flowise Cloud users with chatflows containing password type fields or any HTTP headers. And self hosted Flowise instances exposed to the internet.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | flowise | all versions | 3.1.0npm install flowise@3.1.0 |
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 3.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41266 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-2026-41266 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-41266. 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-2026-41266 in your dependencies?
O3 Security finds CVE-2026-41266 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.