CVE-2026-81866
4.3 · MEDIUMApache NiFi 2.9.0 through 2.11.0 provide Connector configuration update and verification REST API methods that do not enforce authorization checking on Assets and Secrets referenced in proposed con…
Overview
CVE-2026-81866 is a medium-severity vulnerability affecting apache nifi. It was published on September 16, 2026 and has a CVSS 3.1 base score of 4.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.3, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical description
Apache NiFi 2.9.0 through 2.11.0 provide Connector configuration update and verification REST API methods that do not enforce authorization checking on Assets and Secrets referenced in proposed configuration. Updating or verifying a Connector configuration step can apply Asset and Secret references, but framework authorization was limited to write privileges on the Connector itself. As a result of the missing authorization, an authenticated user authorized to modify a Connector, but not authorized to read a referenced Parameter Provider, could apply Secret values backed by that Parameter Provider. The same methods also accepted Asset identifiers without verifying that the Asset belonged to the Connector being configured. Apache NiFi installations that do not implement different levels of authorization across Connectors and Parameter Providers are not subject to this vulnerability, because the framework enforces write permissions on the Connector as the security boundary. Upgrading to A
Remediation
Check the references section for vendor advisories and patches from apache. Update nifi to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| apache | nifi | >= 2.9.0, < 2.12.0 | Affected |
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Frequently asked questions
What is CVE-2026-81866?
CVE-2026-81866 is a medium-severity vulnerability affecting apache nifi. It was published on September 16, 2026 and has a CVSS 3.1 base score of 4.3 (MEDIUM).
How severe is CVE-2026-81866?
This vulnerability has a CVSS 3.1 base score of 4.3, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-81866?
Check the references section for vendor advisories and patches from apache. Update nifi to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-81866?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-81866 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.
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