CVE-2026-58057 (GCVE-0-2026-58057)

Vulnerability from cvelistv5 – Published: 2026-06-28 01:32 – Updated: 2026-06-29 12:25
VLAI
Title
Flowise - Custom MCP Environment Variable Denylist Bypass via Case Sensitivity
Summary
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.
Severity
5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
2.3 (Low)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 12:23 UTC
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7402 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Flowise Flowise Affected: 0 , < 3.1.3 (semver)
Unaffected: 3.1.3 (semver)
    cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-03 00:00
Credits
ashdfrkl
Show details on NVD website
To clipboard 

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