CVE-2026-56277

Flowise - Hardcoded CORS Wildcard in TTS Endpoint

CVSS 6.9 MEDIUMCWE-346

Vexday Risk Score

10Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 6.9EPSS —KEV nãoPoC —Nuclei —Metasploit —Patch referenciado

Lifecycle

30 Jun 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

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.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Affected products

Flowise · Flowise

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References

https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m837-xvxr-vqwg https://www.vulncheck.com/advisories/flowise-hardcoded-cors-wildcard-in-tts-endpoint