Auth bypass in Flowiseai Flowise
CVE-2026-73603
Flowise before 3.1.4 fails to validate chatflow visibility in the unauthenticated text-to-speech endpoint, allowing attackers to abuse private chatflow TTS credentials. Unauthenticated attackers can generate unlimited text-to-speech audio using stored OpenAI or ElevenLabs API keys by providing a valid chatflow UUID, incurring costs on the chatflow owner's account.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (23.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
- Flowiseai Flowise — versions 0, 3.1.4
Weakness classification (CWE)
References
- github.com/FlowiseAI/Flowise/security/advisories/GHSA-8gj2-2cvc-6xx7 (Exploit, vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/flowise-before-credential-abuse-via-text-to-speech (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-73603?
- CVE-2026-73603 is a medium-severity vulnerability in Flowiseai Flowise, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-08-13.
- How severe is CVE-2026-73603?
- Medium severity. CVSS v3 base score is 5.3 out of 10.