nextcloud-mcp-server Package Vulnerability: Critical Endpoint Exposed
- Severity
- HIGH
- Affected component
- nextcloud-mcp-server (pypi)
- Affected versions
- <= 0.117.1
- Patched version
- Not yet available
An early warning has been issued for a critical vulnerability in the nextcloud-mcp-server package. Versions up to 0.117.1 are reportedly affected.
What happened
An early warning has been issued for a critical vulnerability in the nextcloud-mcp-server package. The `POST /webhooks/nextcloud` endpoint in affected versions of the package has no authentication by default, allowing unauthenticated users to delete or corrupt vector embeddings for any user. The `user_id` is taken directly from the attacker-supplied payload. This vulnerability is under investigation and has not been exploited in the wild as of the latest reports.
To assess your exposure, check if your deployment uses the nextcloud-mcp-server package and if the `WEBHOOK_SECRET` is explicitly set. If the `WEBHOOK_SECRET` is unset, your deployment is vulnerable to this issue.
What to do about it
- Ensure that the `WEBHOOK_SECRET` is explicitly set in your deployment to require authentication for the `/webhooks/nextcloud` endpoint.
- Review your deployment configuration to confirm that the `WEBHOOK_SECRET` is correctly implemented.
- Monitor the primary sources for updates on this vulnerability and any official fixes that may be released.
- Consider implementing additional security measures to protect your webhook endpoints until an official fix is available.
How 0Day would have caught this
nextcloud-mcp-server is anywhere in your dependency tree, the engineers who own the affected repositories get a push alert the moment it is flagged — no manual audit to remember to run.Read how this differs from waiting on a scanner to catch a known advisory, or see the exact, read-only access 0Day needs to do this for an organization.
Frequently asked questions
Am I affected?
You are potentially affected if you are using the nextcloud-mcp-server package version 0.117.1 or earlier and the `WEBHOOK_SECRET` is unset in your deployment.
What should I do right now?
Ensure that the `WEBHOOK_SECRET` is explicitly set in your deployment to require authentication for the `/webhooks/nextcloud` endpoint. Monitor the primary sources for updates on this vulnerability.
Is there an official fix available?
No official fix has been published yet. Monitor the primary sources for updates on any official fixes that may be released.