CVE-2026-100868 (GCVE-0-2026-100868)

Vulnerability from cvelistv5 – Published: 2026-09-27 13:09 – Updated: 2026-09-27 13:09
VLAI
Title
Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge
Summary
Penpot before 2.18.0 binds the MCP server plugin WebSocket bridge to all network interfaces without authentication in single-user mode. Unauthenticated attackers on adjacent networks can connect to the WebSocket port to impersonate the Penpot browser plugin, intercept task payloads, and return forged results to the MCP client.
Severity
5.3 (Medium)
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
6.3 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CWE
  • CWE-1327 - Binding to an Unrestricted IP Address
Assigner
References
Impacted products
Vendor Product Version CPE status
penpot penpot Affected: 0 , < 2.18.0 (semver)
guessed Create a notification for this product.
penpot @penpot/mcp Affected: 0 , ≤ 2.15.4 (semver)
guessed Create a notification for this product.
Date Public
2026-09-22 00:00
Credits
George Chen
Show details on NVD website
To clipboard 

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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.
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  • 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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