CVE-2026-54665 Apache NiFi: Missing Validation for Proxy Host Headers
Attackers can manipulate proxy headers to force Apache NiFi to generate malicious redirect URLs, bypassing host validation controls.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-54665?
CVE-2026-54665 is a medium-severity vulnerability in Apache Nifi, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Apache NiFi 0.0.1 through 2.9.0 support building qualified URLs from one of several HTTP request headers that provide an alternative to the standard Host header without validating the values provided. Apache NiFi 1.6.0 introduced a configurable application property to restrict values provided in the HTTP Host header, but did not apply the validation to alternative Proxy and Forwarded headers. The absence of proxy host header validation allowed a client to instruct Apache NiFi web services to construct invalid qualified URLs for redirection or data references. Upgrading to Apache NiFi 2.10.0 is the recommended mitigation, which implements validation for the X-ProxyHost and X-Forwarded-Host HTTP request headers based on the nifi.web.proxy.host property. Enabling header validation requires configuring the application with HTTPS. Reverse proxy servers in front of Apache NiFi are responsible for filtering input request headers and providing allowed values to the application.
Weakness: CWE-346
Which versions are affected by CVE-2026-54665?
3 open source packages ship an affected version, including org.apache.nifi:nifi-jetty and nifi. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
org.apache.nifi:nifi-jetty Maven | All versions | 2.10.0 |
org.apache.nifi:nifi-jetty Maven | All versions | 2.10.0 |
nifi Bitnami | From 0.0.1 | 2.10.0 |
Products include Apache Nifi.
How do I fix CVE-2026-54665?
Upgrade org.apache.nifi:nifi-jetty to 2.10.0 or later.
Is CVE-2026-54665 being exploited?
There is no known exploitation of CVE-2026-54665 in the wild and no public exploit code.
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-2026-54665, CLEANSTART-2026-GJ69600, CLEANSTART-2026-SJ80754, GHSA-8vm2-c32j-mvfr, MINI-4pj2-vgp2-f9fc.