External risk intelligence

Apache Ranger Remote Code Execution via Arbitrary Class Instantiation

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-44416

Apache Ranger is a security framework used for managing data access control across Hadoop ecosystems. While it provides administrative interfaces, it is typically deployed within internal network perimeters to manage data infrastructure, making public internet exposure uncommon in standard enterprise configurations, though it is network-reachable in some specific deployment environments.

Code Injection

Apache Ranger

before 2.9.0

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in the Apache Ranger plugin-schema-registry component that could allow for remote code execution. This could potentially impact systems managing data access control within Hadoop environments. The primary concern at this time is to confirm if this specific component and version are in use within our infrastructure.

Allows attackers to run custom code remotely.
Potential compromise of data access controls.
Confirm Ranger usage and version to assess risk.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending a specially crafted request to the Apache Ranger plugin-schema-registry component. This could allow them to instantiate arbitrary classes, potentially leading to remote code execution.

No authentication or privileges required.
Triggered by arbitrary class instantiation.
Enables remote code execution.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability in the plugin-schema-registry component of Apache Ranger could allow an unauthenticated remote attacker to execute arbitrary code. When supported by the advisory, this could affect the integrity and availability of the Ranger service and any data it manages.

Arbitrary code execution.
Network-based, unauthenticated exploitation.
Compromised service and data integrity.

Operational Fix

Recommended remediation, mitigation, and detection steps

The Apache Ranger component is critical for data access control in Hadoop environments. Given its role, the platform or infrastructure team responsible for Ranger deployments should lead the initial triage. The first practical step is to confirm where Ranger is deployed, assess its network reachability, and identify its business criticality to prioritize remediation efforts.

Platform/Infrastructure team ownership.
Verify Ranger deployment and reachability.
Plan upgrade during maintenance window.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Apache Ranger?

Apache Ranger is a centralized security framework designed to manage and enforce fine-grained access control policies across various components within Hadoop ecosystems. It acts as a gatekeeper, determining who can access specific data sets or perform administrative tasks. Organizations use it to simplify security management for large-scale data environments, ensuring consistent policy application across tools like Hive, HDFS, and HBase.

What does CVE-2026-44416 mean for system security?

This CVE refers to a vulnerability classified as Improper Control of Generation of Code (CWE-94) and Use of Externally-Controlled Input to Select Classes or Code (CWE-470). Essentially, the software can be tricked into loading and running unauthorized programming instructions. Because the plugin-schema-registry component fails to validate what it is being asked to run, an attacker can execute arbitrary code on the host system, bypassing intended security restrictions.

How is this vulnerability triggered?

An attacker triggers this issue by sending a specially crafted request to the plugin-schema-registry component. The flaw exists because the system processes this input without requiring any prior authentication or special user privileges. Normal system operations or standard data queries that do not attempt to force the instantiation of unauthorized classes will not trigger this vulnerability.

Is my Apache Ranger instance at risk?

According to Halo Surface Signal, Apache Ranger is typically deployed within internal network perimeters to protect sensitive data infrastructure, which often limits exposure. However, your risk level depends on your specific deployment, as some environments may make the administrative or registry interfaces network-reachable. You should evaluate whether your instance can be reached from outside your protected internal network.

What steps should I take if I use Apache Ranger?

First, identify all instances of Apache Ranger within your infrastructure and check if they are running a version at or below 2.8.0. Since this is a critical remote code execution vulnerability, prioritize verifying the network reachability of these components. Coordinate with your platform or infrastructure teams to schedule an upgrade to version 2.9.0, which contains the necessary security patches.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.