CVE-2025-66454

Published: Dec 2, 2025Modified: Jun 17, 2026Deferred

6.5

Vector

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

Exploitability: 3.9 / Impact: 2.5

Source: security-advisories@github.com (Secondary)

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.

Related CWEs

CWE-321

Use of Hard-coded Cryptographic Key

The use of a hard-coded cryptographic key significantly increases the possibility that encrypted data may be recovered.

CWE-798

Use of Hard-coded Credentials

The product contains hard-coded credentials, such as a password or cryptographic key.

References (3)

https://github.com/ArcadeAI/arcade-mcp/commit/44660d18ceb220600401303df860a31ca766c817

Source: security-advisories@github.com

https://github.com/ArcadeAI/arcade-mcp/pull/691

Source: security-advisories@github.com

https://github.com/ArcadeAI/arcade-mcp/security/advisories/GHSA-g2jx-37x6-6438

Source: security-advisories@github.com

Timeline

No history available yet.