CVE-2025-66454

MEDIUM EPSS 18.7%
Published Dec 2, 20257mo ago · Modified Jun 17, 20261w ago
6.5 CVSS 3.1
Medium
Find Similar
Published Dec 2, 2025 7mo ago
Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score
6.5
Exploitability
3.9
Impact
2.5
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
18.7% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 2

CWE-321
CWE-798 Use of Hard-coded Credentials Authentication

References 3

  • github.com https://github.com/ArcadeAI/arcade-mcp/commit/44660d18ceb220600401303df860a31ca766c817
  • github.com https://github.com/ArcadeAI/arcade-mcp/pull/691
  • github.com https://github.com/ArcadeAI/arcade-mcp/security/advisories/GHSA-g2jx-37x6-6438

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.