CVE-2026-56277 json
Flowise - Hardcoded CORS Wildcard in TTS Endpoint
published 5mo ago modified 4mo ago also GHSA-m837-xvxr-vqwg , EUVD-2026-40432
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 7%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm flowise 3.1.2
- Flowise Flowise 3.1.2
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | 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 |
| CNA | 4.0 | 6.9 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | flowise | <3.1.2 |
3.1.2 |
Affected products
- Flowise Flowise
Classification
References
-
github.com
/FlowiseAI/Flowise/security/advisories/GHSA-m837-xvxr-vqwg
vendor-advisory, web, mitigation
-
vulncheck.com
/advisories/flowise-hardcoded-cors-wildcard-in-tts-endpoint
third-party-advisory
-
github.com
/FlowiseAI/Flowise
package
Sources
- CVE List CVE-2026-56277
- GitHub Advisory GHSA-m837-xvxr-vqwg
- NVD CVE-2026-56277
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