CVE-2026-56274
Flowise
- Severity
- Critical
- Published
- June 23, 2026
- Last modified
- June 25, 2026
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.
CVSS vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weakness
- CWE-78 OS command injection
References
- github.comExploitThird Party Advisory
- vulncheck.comThird Party Advisory
- github.comExploitThird Party Advisory
Listed in
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