Penpot up to 2.17.x MCP server plugin WebSocket bridge improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.16

Summaryinfo

A vulnerability classified as critical was found in Penpot up to 2.17.x. The affected element is an unknown function of the component MCP server plugin WebSocket bridge. Such manipulation leads to improper authentication. This vulnerability is referenced as CVE-2026-100868. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Penpot up to 2.17.x and classified as critical. Affected by this issue is an unknown function of the component MCP server plugin WebSocket bridge. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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 advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-100868 since 09/27/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 2.18.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Penpot 2.18.0

Timelineinfo

09/27/2026 Advisory disclosed
09/27/2026 +0 days CVE reserved
09/27/2026 +0 days VulDB entry created
09/27/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-100868 (🔒)
GCVE (CVE): GCVE-0-2026-100868
GCVE (VulDB): GCVE-100-410900

Entryinfo

Created: 09/27/2026 15:31
Changes: 09/27/2026 15:31 (75)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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