CVE-2025-62713

Impact

Development mode only. Kottster contains a pre-authentication remote code execution (RCE) vulnerability when running in development mode.

The vulnerability combines two issues:

1. The initApp action can be called repeatedly without checking if the app is already initialized, allowing attackers to create a new root admin account and obtain a JWT token
2. The installPackagesForDataSource action uses unescaped command arguments, enabling command injection

An attacker with access to a locally running development instance can chain these vulnerabilities to:

• Reinitialize the application and receive a JWT token for a new root account
• Use this token to authenticate
• Execute arbitrary system commands through installPackagesForDataSource

Production deployments were never affected.

Patches

Fixed in v3.3.2.

Specifically, @kottster/server v3.3.2 and @kottster/cli v3.3.2 address this vulnerability.

We recommend developers using earlier versions of @kottster/server and @kottster/cli update all the core packages to latest release:

npm install @kottster/common@latest @kottster/cli@latest @kottster/server@latest @kottster/react@latest

Workarounds

• Do not expose development servers to public networks or untrusted users
• Use production mode for any deployment accessible from outside trusted environments

Credit

We sincerely thank Jeongwon Jo (@P0cas) from RedAlert for discovering and responsibly disclosing this vulnerability.