CVE-2026-39816 Apache NiFi: Missing Execute Code Required Permission on TinkerpopClientService
Users without Execute Code permission can execute Groovy scripts via TinkerpopClientService in Apache NiFi installations with fine-grained authorization and the optional graph services extension.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-39816?
CVE-2026-39816 is a high-severity missing authorization vulnerability in Apache Nifi, published on 8 May 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
The optional extension component TinkerpopClientService is missing the Restricted annotation with the Execute Code Required Permission in Apache NiFi 2.0.0-M1 through 2.8.0. The TinkerpopClientService supports configuration of ByteCode Submission for the Script Submission Type, enabling Groovy Script execution in the service prior to submitting the query. The missing Restricted annotation allows users without the Execute Code Permission to configure the Service in installations that use fine-grained authorization and have the optional TinkerpopClientService installed. Apache NiFi installations that do not have the nifi-other-graph-services-nar installed are not subject to this vulnerability. Upgrading to Apache NiFi 2.9.0 is the recommended mitigation.
Weakness: CWE-862
Which versions are affected by CVE-2026-39816?
3 open source packages ship an affected version, including org.apache.nifi:nifi-other-graph-services-nar and nifi. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.apache.nifi:nifi-other-graph-services-nar Maven | From 2.0.0-M1 | 2.9.0 |
org.apache.nifi:nifi-other-graph-services-nar Maven | From 2.0.0-M1 | 2.9.0 |
nifi Bitnami | From 2.0.0 | 2.9.0 |
Products include Apache Nifi.
How do I fix CVE-2026-39816?
Upgrade org.apache.nifi:nifi-other-graph-services-nar to 2.9.0 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-39816 being exploited?
There is no known exploitation of CVE-2026-39816 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Apache Nifi
- CVE-2018-1309 Improper Restriction of XML External Entity Reference in Apache NiFi
- CVE-2017-15697 Apache NiFi XSS issue in context path handling
- CVE-2017-5636 Injection in Apache NiFi
- CVE-2026-68981 Apache NiFi: Uncontrolled Resource Consumption through Decompression of HTTP Requests
- CVE-2023-36542 Apache NiFi: Potential Code Injection with Properties Referencing Remote Resources
Sources
Also known as BIT-nifi-2026-39816, GHSA-2j9m-25xv-mp6r, MINI-3hc4-25m5-cfpx.