External risk intelligence

Neptune Connector Remote Property Access Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.4)

CVE-2026-77810

The vulnerability exists within a federated query connector used to bridge Athena and Neptune. These connectors typically operate within a private cloud environment, requiring authenticated access to the Athena service and specific internal configurations to reach the connector's Lambda infrastructure, making direct public internet exposure uncommon.

Halo Surface Signal: 2 out of 5 — less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A security vulnerability has been identified in the Neptune connector for Athena Federated Query. This issue could allow a user with access to Neptune to gain unauthorized access to sensitive information within the Lambda function that powers the connector. Addressing this requires upgrading to a specific version of the aws-athena-query-federation software.

Connector flaw allows data access via Neptune.
Could expose sensitive Lambda properties.
Confirm relevance and exposure of Neptune connector.

Attack Path

How an attacker could exploit the issue

An attacker with authenticated access to Amazon Athena could potentially compromise the Lambda function powering the Neptune connector. This could grant them access to sensitive information within the Lambda environment.

Authenticated access to Athena required.
Triggered by querying the Neptune connector.
Risk of access to sensitive Lambda properties.

Live Threat

Current exploitation, exposure, and threat context

A user authenticated to Neptune through Athena Federated Query could potentially access properties within the Lambda function that powers the connector. This exposure is contingent on the user having the necessary access to Neptune via this specific query method.

Connector's Lambda function properties.
Access via authenticated query.
Unauthorized information exposure.

Operational Fix

Recommended remediation, mitigation, and detection steps

Ownership of this vulnerability likely falls to the AWS Athena Federated Query platform team or the specific application team managing the Neptune connector, as it impacts data access through a specialized integration. The immediate priority is to identify all instances of the affected connector, confirm their reachability and business criticality, and locate the accountable owner to plan for remediation.

Platform or application teams own the issue.
Verify connector instances and business impact.
Coordinate remediation with vendor updates.

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 the Neptune connector for Athena Federated Query?

This software component acts as a bridge that allows Amazon Athena to run SQL queries against data stored in Amazon Neptune, a graph database service. It runs on AWS Lambda, providing the necessary compute power to translate and execute queries across these different data environments.

What does CWE-95 mean in the context of CVE-2026-77810?

CWE-95 refers to Improper Neutralization of Directives in Dynamically Evaluated Code, often known as an injection vulnerability. In this CVE, it means the connector fails to safely handle input, allowing a user to break out of expected query boundaries and execute unintended commands or access data within the underlying Lambda environment.

How is the vulnerability triggered?

An attacker must be authenticated to Athena and have permission to query the Neptune connector. The issue is triggered by crafting specific queries that exploit the connector's logic. Simply having access to the Neptune database or Athena generally is not enough; the attacker must use this specific federated query path to reach the affected Lambda function.

Is my system exposed to this vulnerability?

According to Halo Surface Signal, this vulnerability is classified as unlikely to be directly exposed to the public internet. Because the connector operates within a private cloud environment, it typically requires authenticated access to the Athena service and specific internal configuration to reach the infrastructure, limiting the potential attack surface.

How do I fix CVE-2026-77810?

To secure your environment, you need to update the aws-athena-query-federation software to version 2026.30.1 or later. Start by identifying all instances of the Neptune connector in use, coordinate with your platform or application teams, and apply the update to the Lambda functions powering those connectors.

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.