CVE-2026-54665
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. Limited direct impact.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 6.3 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-346
- Record status
- Analyzed
Affected
- Apache Nifi < 2.10.0
Attack profile CVSS 4.0 · 6.3
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- Present
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Raw vector
CVSS:4.0/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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-54665.md and follow it. Check whether this project is affected by CVE-2026-54665. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
