CVE-2026-58057CWE-178

Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity

Low · published June 28, 2026

CVSS v4.0
2.3
EPSS
2%
Percentile
75.0
In the wild
Unconfirmed
What it is

Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.

The record
Technical detail
CVSS v4.0
2.3 · LOW
Vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
EPSS
0.01556 · 75.0th percentile
Weakness
CWE-178 · Improper Handling of Case Sensitivity
Published
2026-06-28T01:32Z
EPSS history
Timeline
  • 28 JUN 01:32Z
    Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity
    cvelistv5