6.3
MEDIUM CVSS 4.0
CVE-2026-54665
Apache NiFi: Missing Validation for Proxy Host Headers
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.

INFO

Published Date :

June 22, 2026, 8:17 a.m.

Last Modified :

June 23, 2026, 7:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-54665 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Apache nifi
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM f0158376-9dc2-43b6-827c-5f631a4d8d09
CVSS 4.0 MEDIUM [email protected]
Solution
Upgrade Apache NiFi and enable header validation using HTTPS and reverse proxy configurations.
  • Upgrade Apache NiFi to version 2.10.0 or later.
  • Configure the nifi.web.proxy.host property.
  • Enable header validation for X-ProxyHost and X-Forwarded-Host.
  • Configure reverse proxy servers to filter request headers.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-54665.

URL Resource
https://lists.apache.org/thread/y0yoblon8f6dp00qz5r90cxq5n6g4j6k Vendor Advisory Mailing List
http://www.openwall.com/lists/oss-security/2026/06/20/7 Third Party Advisory Mailing List
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-54665 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-54665 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-54665 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-54665 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Jun. 23, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
    Added CPE Configuration OR *cpe:2.3:a:apache:nifi:*:*:*:*:*:*:*:* versions from (including) 0.0.1 up to (excluding) 2.10.0
    Added Reference Type Apache Software Foundation: https://lists.apache.org/thread/y0yoblon8f6dp00qz5r90cxq5n6g4j6k Types: Mailing List, Vendor Advisory
    Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2026/06/20/7 Types: Mailing List, Third Party Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 22, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-54665', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-22T16:09:44.185547Z'}
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Jun. 22, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/06/20/7
  • New CVE Received by [email protected]

    Jun. 22, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Apache Software Foundation', 'product': 'Apache NiFi', 'versions': [{'status': 'affected', 'version': '0.0.1', 'lessThan': '2.10.0', 'versionType': 'semver'}], 'packageName': 'org.apache.nifi:nifi-jetty', 'collectionURL': 'https://repo.maven.apache.org/maven2', 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:A/V:D/RE:L/U:Green
    Added CWE CWE-346
    Added Reference https://lists.apache.org/thread/y0yoblon8f6dp00qz5r90cxq5n6g4j6k
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.