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

Vulnerability from cvelistv5 – Published: 2026-06-28 01:32 – Updated: 2026-06-28 01:32
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
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
References
Impacted products
Vendor Product Version
Flowise Flowise Affected: 0 , < 3.1.3 (semver)
Unaffected: 3.1.3 (semver)
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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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.