CVE-2026-56274
CRITICALFlowise - Remote Code Execution via MCP Security Bypass in validateCommandFlags and validateArgsForLocalFileAccess
Title source: cnaDescription
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.
References (2)
Core 2
Core References
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-m99r-2hxc-cp3q)
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m99r-2hxc-cp3q
Third Party Advisory third-party-advisory
VulnCheck Advisory: Flowise - Remote Code Execution via MCP Security Bypass in validateCommandFlags and validateArgsForLocalFileAccess
https://www.vulncheck.com/advisories/flowise-remote-code-execution-via-mcp-security-bypass-in-validatecommandflags-and-validateargsforlocalfileaccess
Scores
CVSS v3
9.9
EPSS
0.0327
EPSS Percentile
87.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
total
Details
CWE
CWE-78
Status
published
Products (5)
Flowise/Flowise
< 3.1.2
Flowise/Flowise
3.1.2
Flowise/Flowise Components
< 3.1.2
Flowise/Flowise Components
3.1.2
flowiseai/flowise
< 3.1.2
Published
Jun 23, 2026
Tracked Since
Jun 23, 2026