CVE-2023-24831 - How a Simple Authentication Bug Let Attackers in Apache IoTDB Grafana Connector Walk Right In

Security is only as strong as its weakest link. Recently, a critical vulnerability was found in the Apache IoTDB Grafana Connector. This open-source software is used by thousands to connect time-series data (from Apache IoTDB) to Grafana dashboards for monitoring and visualization. However, between versions .13. and .13.3, a dangerous flaw (CVE-2023-24831) allowed attackers to log in without any authorization – essentially breaking the lock on the door.

In this long read, we'll explain what went wrong, how it worked (with clear code snippets), why it was dangerous, how to fix it, and share references for those who want to dig deeper.

What Is Apache IoTDB & The Grafana Connector?

Apache IoTDB is a high-performance database for time-series data, often used in IoT, monitoring, and data-intensive environments.

The Grafana Connector is a plugin (see official docs) to hook IoTDB data into Grafana, a popular dashboard service for visualizing metrics.

What Was the Vulnerability (CVE-2023-24831)?

It boils down to improper authentication. The connector did NOT properly check users' credentials.

Official Description

> "Improper Authentication vulnerability in Apache Software Foundation Apache IoTDB Grafana Connector allows attackers to login without authorization..."

(Source: NVD listing for CVE-2023-24831)

Who is Affected?

If you use Apache IoTDB with its Grafana Connector (versions .13. - .13.3), you are at risk. Even if you have Grafana secure and IoTDB secure on their own, the connector might expose your data.

The "Authentication" Code

Normally, when an external app connects to a database, it must pass a username and password that are verified.

In vulnerable versions, the authentication function kind of... does nothing.

// Pseudocode illustrating the flaw

public boolean authenticate(String username, String password) {
    // Vulnerable versions had logic similar to this:
    return true;
}

Instead of checking if the username and password are valid, it always returned true – allowing *anyone* in, as long as they provided *anything* (or even nothing!).

Real Example

From Github diff:

Before the fix

public boolean checkUser(String user, String password) {
    // always returns true
    return true; 
}

After the fix

public boolean checkUser(String user, String password) {
    // real check that user and password actually match
    return authenticateWithIoTDB(user, password);
}

Here’s how an attacker could exploit this

1. Install/Find a vulnerable Grafana Connector (.13.-.13.3) talking to IoTDB.
2. Craft an HTTP(S) request that simulates a login — just pass any username/password.
3. Connector passes the connection, regardless. Attacker gets access to ALL time-series data visible via this plugin.
4. Attacker may be able to read or possibly write/modify data, depending on what the plugin's permissions allow.

A request like

POST /login
{
    "user": "admin",
    "password": "any-wrong-password"
}

Or even

POST /login
{
    "user": "",
    "password": ""
}


…would still be accepted.

Why Is This Bad?

- No authentication at all: Anyone, anywhere, as long as they can reach the connector (internal network, or perhaps via the internet), could access sensitive data meant to be private.
- Bypassing existing security: Even if your Grafana and IoTDB were safe, the connector was a hidden backdoor.

IMMEDIATELY upgrade to at least version .13.4 of the Apache IoTDB Grafana Connector.

- Upgrade Instructions
2. Restrict access: Make sure only trusted nodes can connect to your Grafana Connector – if possible, firewall it off while you patch.
3. Audit logs: Check for unusual connections or data queries during the period you were running affected versions.

- CVE-2023-24831 at NVD (National Vulnerability Database)
- Apache IoTDB Github Issue Discussion
- Fix PR on Github
- Release Notes for .13.4
- Apache IoTDB Official Website
- Grafana Data Source Documentation
- Grafana Official Site

Conclusion

CVE-2023-24831 is a textbook reminder: even mature, reputable software can fall to the simplest mistakes, like skipping authentication. If you run Apache IoTDB with Grafana Connector, check your versions *now* and upgrade to .13.4 or later. Never assume plugins are covered by your main system's security!

If you want a technical deep dive, the references above have all the details. And remember – one little return true; can bring the strongest system to its knees.


*Stay safe out there, and keep your software up to date!*

Timeline

Published on: 04/17/2023 07:15:00 UTC
Last modified on: 04/28/2023 15:56:00 UTC