CVE-2025-66454 | BDVDB-2026-303699 Detail

ArcadeAIarcade-mcp

Description#

Arcade MCP allows you to to create, deploy, and share MCP Servers. Prior to 1.5.4, the arcade-mcp HTTP server uses a hardcoded default worker secret ("dev") that is never validated or overridden during normal server startup. As a result, any unauthenticated attacker who knows this default key can forge valid JWTs and fully bypass the FastAPI authentication layer. This grants remote access to all worker endpoints—including tool enumeration and tool invocation—without credentials. This vulnerability is fixed in 1.5.4.

Impact#

Per CVSS v3.1: confidentiality impact low, integrity impact low, availability impact none. Attack vector: network.

Weaknesses#

CWE-321 Use of Hard-coded Cryptographic Key
CWE-798 Use of Hard-coded Credentials

References#

Exploit#

No public exploit known

History#

Version 12025-12-02Record published in the CVE List.

Published

Published: 2025-12-02
Last modified: 2025-12-02

Vendor information

Vendor: ArcadeAI
Product: arcade-mcp

All ArcadeAI vulnerabilities

Score

6.5 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 26.8.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Hard-coded Credentials

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 1.5.4
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

6.5 Medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	None
Scope	Unchanged
Confidentiality	Low
Integrity	Low
Availability	None

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).