How severe is GHSA-m837-xvxr-vqwg?

No CVSS score has been assigned to GHSA-m837-xvxr-vqwg yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-m837-xvxr-vqwg?

GHSA-m837-xvxr-vqwg affects the following packages: flowise (npm). Ecosystems affected: npm.

How do I fix GHSA-m837-xvxr-vqwg?

Update flowise to 3.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m837-xvxr-vqwg is resolved across your whole dependency graph.

How do I detect GHSA-m837-xvxr-vqwg in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flowise. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-m837-xvxr-vqwg if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-m837-xvxr-vqwg?

O3 pinpoints whether GHSA-m837-xvxr-vqwg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-m837-xvxr-vqwg actively exploited in the wild?

No public exploit code has been indexed for GHSA-m837-xvxr-vqwg yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-m837-xvxr-vqwg published, and has it been updated?

GHSA-m837-xvxr-vqwg was published on May 20, 2026 and was last updated on May 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

GHSA-m837-xvxr-vqwg

Flowise: Hardcoded CORS wildcard on TTS endpoint enables cross-origin credential abuse from any webpage

Published

May 20, 2026

Updated

May 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Blast Radius

1 pkg affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

flowisenpm

3Kdownloads / week

Description

Summary

The TTS generation endpoint sets Access-Control-Allow-Origin: * as a hardcoded response header, independent of the server's CORS configuration. This enables any webpage to make cross-origin requests to generate speech using stored credentials.

Root Cause

// packages/server/src/controllers/text-to-speech/index.ts:83
res.setHeader('Access-Control-Allow-Origin', '*')
res.setHeader('Access-Control-Allow-Headers', 'Cache-Control')

Impact

Cross-origin credential abuse — any webpage can trigger TTS using stored credentials
Bypasses the server's CORS policy (getCorsOptions()) which is otherwise restrictive by default
Combined with Finding 3 (TTS credential abuse), enables drive-by credential abuse via malicious webpages

Suggested Fix

Remove the hardcoded CORS wildcard and let the server's CORS middleware handle the headers:

// Remove these lines:
// res.setHeader('Access-Control-Allow-Origin', '*')
// res.setHeader('Access-Control-Allow-Headers', 'Cache-Control')

References

packages/server/src/controllers/text-to-speech/index.ts line 83

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`flowise`	all versions	3.1.2

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flowise. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update flowise to 3.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m837-xvxr-vqwg 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 pinpoints whether GHSA-m837-xvxr-vqwg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-m837-xvxr-vqwg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary The TTS generation endpoint sets `Access-Control-Allow-Origin: *` as a hardcoded response header, independent of the server's CORS configuration. This enables any webpage to make cross-origin requests to generate speech using stored credentials. ### Root Cause ```typescript // packages/server/src/controllers/text-to-speech/index.ts:83 res.setHeader('Access-Control-Allow-Origin', '*') res.setHeader('Access-Control-Allow-Headers', 'Cache-Control') ``` ### Impact - Cross-origin credential abuse — any webpage can trigger TTS using stored credentials - Bypasses the server's CORS po

O3 Security · Impact-Aware SCA

Is GHSA-m837-xvxr-vqwg in your dependencies?

O3 detects GHSA-m837-xvxr-vqwg across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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