CVE-2026-100868CWE-1327

CVE-2026-100868

Medium · published September 27, 2026

CVSS v3.1
6.3
EPSS
0%
Percentile
16.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.3 · MEDIUM
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS v4.0
5.3 · 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
EPSS
0.00257 · 16.5th percentile
Weakness
CWE-1327 · Binding to an Unrestricted IP Address
Published
2026-09-27T17:16Z
References (7)
https://github.com/penpot/penpot · [email protected]https://github.com/penpot/penpot/blob/1d2c37e52c733f74017d90b0fd1ae2d074a5c33d/mcp/packages/server/src/PluginBridge.ts#L52 · [email protected]https://github.com/penpot/penpot/commit/b5274a44766d095247037be18c1d1918ac67ddeb · [email protected]https://github.com/penpot/penpot/security/advisories/GHSA-22qr-rp27-j9wm · [email protected]https://github.com/penpot/penpot/security/advisories/GHSA-ch2q-6x56-qg5r · [email protected]https://www.vulncheck.com/advisories/penpot-before-2.18.0-unauthenticated-websocket-access-via-mcp-bridge · [email protected]https://github.com/penpot/penpot/security/advisories/GHSA-ch2q-6x56-qg5r · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 29 SEP 03:24Z
    EPSS moved — → 0%
    epss
  • 27 SEP 13:09Z
    Penpot before 2.18.0 Unauthenticated WebSocket Access via MCP Bridge
    cvelistv5