Auth bypass in Flowiseai Flowise
CVE-2026-70636
Flowise through 3.1.4 contains an authentication bypass vulnerability that allows unauthenticated attackers to access the OAuth2 credential refresh endpoint by exploiting prefix-based whitelist matching in the authentication middleware defined in packages/server/src/utils/constants.ts. Attackers can send a POST request to the oauth2-credential refresh route with a trailing credential identifier to bypass all authentication and authorization checks, triggering unauthorized OAuth token rotation against credentials belonging to any workspace and potentially disrupting dependent OAuth integrations. This is a bypass of CVE-2026-41273.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.007 (51.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
- Flowiseai Flowise — versions 0
Weakness classification (CWE)
References
- flowiseai.com/sunset (vendor-advisory, Not Applicable)
- github.com/Caycon/cve-advisories/blob/main/2026/Flowise/CVE-2026-70636.md (Exploit, technical-description, Third Party Advisory, exploit)
- www.vulncheck.com/advisories/flowise-authentication-bypass-via-oauth2-credentia… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-70636?
- CVE-2026-70636 is a high-severity vulnerability in Flowiseai Flowise, classified under Missing Authorization. CVSS score: 7.5/10. Published 2026-08-06.
- How severe is CVE-2026-70636?
- High severity. CVSS v3 base score is 7.5 out of 10.