CVE-2026-56277 Flowise - Hardcoded CORS Wildcard in TTS Endpoint
Attackers can bypass CORS restrictions to trigger TTS generation using stored credentials via cross-origin requests.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-56277?
CVE-2026-56277 is a medium-severity vulnerability in Flowiseai Flowise, published on 30 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Flowise before 3.1.2 sets Access-Control-Allow-Origin to a hardcoded wildcard (*) on its text-to-speech (TTS) generation endpoint (packages/server/src/controllers/text-to-speech/index.ts), independent of the server's configured CORS policy. This bypasses the server's otherwise restrictive default CORS configuration (getCorsOptions()) and allows any webpage to make cross-origin requests that trigger TTS generation using stored credentials, enabling drive-by cross-origin credential abuse.
Weakness: CWE-346
Which versions are affected by CVE-2026-56277?
2 open source packages ship an affected version, including flowise. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
flowise npm | All versions | 3.1.2 |
flowise npm | All versions | 3.1.2 |
Products include Flowiseai Flowise.
How do I fix CVE-2026-56277?
Upgrade flowise to 3.1.2 or later.
Is CVE-2026-56277 being exploited?
There is no known exploitation of CVE-2026-56277 in the wild and no public exploit code.
Other vulnerabilities in Flowiseai Flowise
- CVE-2025-71338 Flowise through 2.2.7 - Arbitrary File Write to Remote Code Execution via document-store API
- CVE-2026-40933 Flowise: Authenticated RCE Via MCP Adapters
- CVE-2025-61913 Flowise is vulnerable to arbitrary file read, arbitrary file write
- CVE-2025-59528 Flowise has Remote Code Execution vulnerability
- CVE-2026-52098 Code injection in n/a
Sources
Also known as GHSA-8m62-6r3h-3x25, GHSA-m837-xvxr-vqwg.