What is CVE-2026-56274?

CVE-2026-56274 is a critical-severity vulnerability in Flowise, classified under OS Command Injection. CVSS score: 9.9/10. Published 2026-06-23.

How severe is CVE-2026-56274?

Critical severity. CVSS v3 base score is 9.9 out of 10.

RCE in Flowise

CVE-2026-56274

Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation and a regex bypass in local file access restrictions. An attacker with a Flowise account…

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.033 (87.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Flowise — versions 0, 3.1.2
Flowise Components — versions 0, 3.1.2
Flowiseai Flowise

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

disclosure@vulncheck.com (Exploit, vendor-advisory, Third Party Advisory)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-56274?: CVE-2026-56274 is a critical-severity vulnerability in Flowise, classified under OS Command Injection. CVSS score: 9.9/10. Published 2026-06-23.
How severe is CVE-2026-56274?: Critical severity. CVSS v3 base score is 9.9 out of 10.