CVE-2024-39676: Apache Pinot Information Disclosure Flaw

CVE-2024-39676 Overview

CVE-2024-39676 is an information disclosure vulnerability in Apache Pinot, an open-source distributed online analytical processing (OLAP) datastore. The flaw affects Apache Pinot versions from 0.1 before 1.0.0. Unauthenticated attackers can issue a request to the /appconfigs endpoint on the Pinot controller and retrieve sensitive system, environment, and configuration data. Disclosed information includes system architecture, operating system version, JVM maxHeapSize, and Pinot configuration values such as ZooKeeper paths. The issue is tracked under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.

Critical Impact

Remote attackers can query an unauthenticated controller endpoint to harvest infrastructure metadata and configuration paths useful for follow-on attacks against Apache Pinot deployments.

Affected Products

• Apache Pinot versions 0.1 through versions before 1.0.0
• Pinot Controller component exposing the /appconfigs REST endpoint
• Deployments without Role-Based Access Control (RBAC) configured

Discovery Timeline

• 2024-07-24 - CVE-2024-39676 published to NVD
• 2025-03-14 - Last updated in NVD database

Technical Details for CVE-2024-39676

Vulnerability Analysis

Apache Pinot exposes administrative REST endpoints on its controller service. The /appconfigs endpoint returns a JSON document describing the runtime context of the controller process. Before version 1.0.0, this endpoint did not enforce authentication or authorization by default. Any actor able to reach the controller over the network could retrieve the response.

The disclosed payload includes operating system name and version, CPU architecture, JVM heap configuration including maxHeapSize, and Pinot-specific configuration such as ZooKeeper connection paths. Attackers use this telemetry to fingerprint the deployment, identify supporting infrastructure like ZooKeeper clusters, and plan further intrusion attempts against connected services.

Root Cause

The root cause is a missing authorization control on a sensitive administrative endpoint. The controller registered /appconfigs as a publicly accessible route without binding it to an authentication filter. Apache Pinot did not ship a default administrator role, so even operators who enabled basic authentication had to manually scope each endpoint.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker sends an HTTP GET request to the controller path /appconfigs. The controller responds with the configuration document. The vulnerability impacts confidentiality only; integrity and availability are not affected, since the endpoint is read-only.

The vulnerability mechanism does not require crafted payloads or exploitation tooling. See the Apache mailing list advisory and the Openwall OSS Security discussion for vendor-published technical details.

Detection Methods for CVE-2024-39676

Indicators of Compromise

• HTTP GET requests to the Pinot controller path /appconfigs originating from unexpected source addresses
• Controller access logs showing unauthenticated 200 responses to /appconfigs requests
• Outbound enumeration patterns that follow a successful /appconfigs query, such as probes against ZooKeeper hosts referenced in the response

Detection Strategies

• Inspect Pinot controller access logs for requests to /appconfigs and correlate them against authorized administrator source ranges
• Deploy web application firewall or reverse proxy rules that alert when administrative endpoints are accessed without an authentication header
• Hunt for reconnaissance behavior chaining /appconfigs responses with subsequent connection attempts to disclosed ZooKeeper paths

Monitoring Recommendations

• Forward Pinot controller logs to a centralized logging or SIEM platform and create alerts for anonymous access to administrative routes
• Track configuration drift on Pinot RBAC settings to ensure authentication remains enforced after deployments and upgrades
• Monitor network flows between the Pinot controller and untrusted network segments to identify exposure of management endpoints

How to Mitigate CVE-2024-39676

Immediate Actions Required

• Upgrade Apache Pinot to version 1.0.0 or later, which introduces RBAC enforcement on administrative endpoints
• Enable basic authentication and configure RBAC as described in the Apache Pinot basic authentication guide
• Assign an administrator role to authorized operators and restrict /appconfigs access to that role
• Block external network access to the Pinot controller management port until access control is verified

Patch Information

Apache fixed the issue in Apache Pinot 1.0.0 by routing administrative endpoints, including /appconfigs, through the RBAC subsystem. Operators must both upgrade and explicitly configure RBAC, since the fixed release does not ship a default administrator role. The Apache Pinot project has stated that a default admin role is planned for a future release. Refer to the Apache mailing list advisory for the official notice.

Workarounds

• Place the Pinot controller behind a reverse proxy that enforces authentication on all /appconfigs and administrative paths
• Restrict controller access to trusted management networks using firewall rules or network segmentation
• Deny /appconfigs at the load balancer or ingress layer if administrative tooling does not require the endpoint

# Example nginx reverse proxy snippet restricting /appconfigs to an internal CIDR
location /appconfigs {
    allow 10.0.0.0/24;
    deny all;
    auth_basic "Pinot Admin";
    auth_basic_user_file /etc/nginx/.htpasswd;
    proxy_pass http://pinot-controller:9000;
}