What’s Vulnerable › Vulnerabilities

CVE-2026-56271: Flowise - Weak Default JWT Secrets in Authentication Middleware

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-12 · updated 2026-10-25
• Weakness: CWE-321

Description

Flowise before 3.1.0 (affected versions 3.0.13 and earlier) uses weak hardcoded default JWT secrets ('auth_token', 'refresh_token') and default audience and issuer values ('AUDIENCE', 'ISSUER') in the enterprise passport authentication middleware (packages/server/src/enterprise/middleware/passport/index.ts). When the corresponding environment variables (JWT_AUTH_TOKEN_SECRET, JWT_REFRESH_TOKEN_SECRET, JWT_AUDIENCE, JWT_ISSUER) are not set, the application silently falls back to these publicly known defaults, allowing an attacker to forge valid JWTs and impersonate any user, including administrators, resulting in authentication bypass.

Affected products

• FlowiseAI Flowise: before 3.1.0 — fixed in 3.1.0

How to fix

Upgrade to a fixed version: FlowiseAI Flowise 3.1.0. Check the vendor advisory for mitigations.

References

• https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-cc4f-hjpj-g9p8
• https://www.vulncheck.com/advisories/flowise-weak-default-jwt-secrets-in-authentication-middleware

Get alerted when CVE-2026-56271 or the next vulnerability affects your stack