PT-2026-51507 · Flowise · Flowise

Cn-Panda · Published 2026-06-23 · Updated 2026-06-23 · CVE-2026-56274

NVD

CVSS v3.1

9.9

Critical

Base vector

AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

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 of any role, or API access with view/update permissions for chatflows, can configure a malicious MCP server to bypass the validateCommandFlags blocklist (for example, 'docker build' is not blocked, and 'npx --yes' is not blocked while only '-y' is) and the validateArgsForLocalFileAccess checks, resulting in execution of arbitrary commands on the Flowise host.

Exploit

Fix

OS Command Injection

Weakness Enumeration

CWE-78

Related Identifiers

CVE-2026-56274

Affected Products

Flowise

References · 3

• 🔥 https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m99r-2hxc-cp3q · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-56274 · Security Note
• https://vulncheck.com/advisories/flowise-remote-code-execution-via-mcp-security-bypass-in-validatecommandflags-and-validateargsforlocalfileaccess · Note