What is CVE-2025-8943?

CVE-2025-8943 is a critical-severity vulnerability in Flowiseai Flowise, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2025-08-14.

How severe is CVE-2025-8943?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2025-8943 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Flowiseai Flowise

CVE-2025-8943

The Custom MCPs feature is designed to execute OS commands, for instance, using tools like `npx` to spin up local MCP Servers. However, Flowise's inherent authentication and authorization model is minimal and lacks role-based access controls (RBAC). Furthermore, in Flowise versions before 3.0.1 the default installation operates without authentication unless explicitly configured. This combination allows unauthenticated network attackers to execute unsandboxed OS commands.

Vulnerability class: Broken Authentication

EPSS: 0.663 (99.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Flowiseai Flowise

Weakness classification (CWE)

Public proof-of-concept exploits

References

reefs@jfrog.com (Exploit, Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2025-8943?: CVE-2025-8943 is a critical-severity vulnerability in Flowiseai Flowise, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2025-08-14.
How severe is CVE-2025-8943?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-8943 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.