CVE-2026-6599 (GCVE-0-2026-6599)

Vulnerability from cvelistv5 – Published: 2026-04-20 03:00 – Updated: 2026-04-20 03:00
VLAI?
Title
langflow-ai langflow Model Context Protocol Configuration API mcp_projects.py install_mcp_config injection
Summary
A vulnerability was detected in langflow-ai langflow up to 1.8.3. The impacted element is the function get_client_ip/install_mcp_config of the file src/backend/base/langflow/api/v1/mcp_projects.py of the component Model Context Protocol Configuration API. Performing a manipulation of the argument X-Forwarded-For results in injection. The attack may be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Severity ?
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
6.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R
6.3 (Medium)
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R
CWE
Assigner
References
Impacted products
Vendor Product Version
langflow-ai langflow Affected: 1.8.0
Affected: 1.8.1
Affected: 1.8.2
Affected: 1.8.3
    cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Eric-f (VulDB User) VulDB CNA Team
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    "state": "PUBLISHED"
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}


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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.



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