CVE-2026-100868

Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge

Published Sep 27, 2026 CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Penpot
Penpot mcp
Penpot penpot
Vendors & Products Penpot
Penpot mcp
Penpot penpot
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
Title Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge
First Time appeared Kaleidos
Kaleidos penpot
Weaknesses CWE-1327
CPEs cpe:2.3:a:kaleidos:penpot:*:*:*:*:*:*:*:*
Vendors & Products Kaleidos
Kaleidos penpot
References
Metrics cvssV3_1

{'score': 6.3, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'}

cvssV4_0

{'score': 5.3, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 8, 2026, 3:22 PM
Reserved
Sep 27, 2026, 12:20 AM
Status
Deferred
Published
Sep 27, 2026, 1:16 PM
Modified
Oct 8, 2026, 4:17 PM