Key points
- The flaw affects Amazon Neptune engine versions 1.2.0.0 through 1.5.0.0 and involves unsafe deserialization.
- Attackers need valid data-plane permissions to trigger the bug and gain remote code execution.
- AWS released patched versions 1.4.7.1, 1.4.8.1 and 1.5.0.0 to address the vulnerability.
The short version
- Amazon Neptune contains a critical deserialization flaw in its Gremlin graph-import component.
- An authenticated user with standard database permissions can execute arbitrary code remotely.
- AWS has released engine updates that fix the issue for manual and auto-upgrade customers.
The details
Amazon Neptune contains a critical vulnerability in its Gremlin graph-import component, according to the National Vulnerability Database record for CVE-2026-110812. The flaw allows an authenticated remote actor with standard database permissions to execute arbitrary code and access internal service credentials. The National Vulnerability Database rates the issue as critical with a CVSS score of 9.9.
The weakness stems from the deserialization of untrusted data, classified under CWE-502 and CWE-918. An attacker who has obtained valid credentials for the database can submit a request that causes the query engine to process input unsafely. This unsafe processing can lead to unintended activity within the query engine environment, effectively granting the attacker control over that execution space.
AWS Security Bulletin 2026-136-AWS confirms the issue relates to Apache TinkerPop functionality used by Amazon Neptune. The bulletin states that an authenticated principal with Neptune data-plane permissions could trigger the flaw. This means that simply having access to run queries against the graph database is sufficient to exploit the vulnerability, provided the user can submit the specific malicious input.
The context
The vulnerability affects Amazon Neptune engine versions greater than or equal to 1.2.0.0, according to the AWS advisory. This includes a wide range of deployments that may not have been updated to the latest minor releases. The issue was addressed in engine versions 1.4.7.1, 1.4.8.1 and 1.5.0.0.
Customers who have enabled auto minor version upgrades will receive the patch during their next scheduled maintenance window. Those who manage engine versions manually must initiate the upgrade process themselves. The AWS advisory published on October 15, 2026, recommends upgrading to the corresponding patched version for each engine line to mitigate the risk.
What to watch
Organizations should monitor their Neptune clusters for any unusual query patterns or unexpected process activity within the engine environment. Security teams should verify that all database instances are running one of the patched versions: 1.4.7.1, 1.4.8.1 or 1.5.0.0.
Administrators should also review access logs for any authenticated users who have data-plane permissions but do not require graph-import capabilities. Restricting these permissions can reduce the attack surface while upgrades are being planned or executed.
What it means for organisations
Teams usually need to identify which internal applications or third-party suppliers hold data-plane permissions for graph databases. Security leaders should ask whether any external vendors have direct query access to production clusters. Database administrators must verify that least-privilege policies are enforced, ensuring that only trusted principals can submit import requests. Incident response plans should be reviewed to include scenarios where authenticated users exploit deserialization flaws. Communication with engineering teams is essential to prioritize patching without disrupting critical business operations.
What to do and how to stay safe: Amazon Neptune
- Audit all IAM roles and database credentials to ensure only trusted principals have Neptune data-plane permissions.
- Upgrade Amazon Neptune clusters to engine versions 1.4.7.1, 1.4.8.1 or 1.5.0.0 as soon as maintenance windows allow.
- Enable auto minor version upgrades for future clusters to ensure automatic application of security patches.
- Monitor database logs for suspicious query activity that could indicate an attempt to exploit the deserialization flaw.
Step-by-step guide: Automatic Software Updates: Definition, Mechanics and Hidden Risks
General security guidance from the TechSec Headlines newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-110812?
It is a critical deserialization vulnerability in the Gremlin graph-import component of Amazon Neptune that allows code execution.
Which Amazon Neptune versions are affected?
Engine versions greater than or equal to 1.2.0.0 are affected, including versions up to 1.5.0.0 before the patch.
How can an attacker exploit this flaw?
An attacker needs to be authenticated and have Neptune data-plane (query) permissions to submit malicious requests.
