CVE-2026-91866 Apache Neethi: Crafted policies cause unbounded work during intersection leading to denial of service
Attackers can cause denial of service by submitting crafted WS-Policy documents that trigger exponential CPU usage in Apache Neethi.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-91866?
CVE-2026-91866 is a high-severity denial of service vulnerability in Apache Neethi, published on 21 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A specially crafted pair of WS-Policy documents can force Neethi's policy-intersection to do exponential amounts of work, pinning the CPU for a long time (denial of service). Users are recommended to upgrade to version 3.2.4, which fixes this issue.
Weakness: CWE-770
Which versions are affected by CVE-2026-91866?
It affects 1 product.
Products include Apache Neethi.
How do I fix CVE-2026-91866?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-91866 being exploited?
There is no known exploitation of CVE-2026-91866 in the wild and no public exploit code.
Other vulnerabilities in Apache Neethi
- CVE-2026-91863 Apache Neethi: Uncontrolled recursion while parsing crafted WS-Policy documents allows denial of service
- CVE-2026-91864 Apache Neethi: Crafted WS-Policy documents bypass element/attribute limits causing memory exhaustion
- CVE-2026-91865 Apache Neethi: Crafted policy references cause exponential expansion during normalization leading to denial of service
- CVE-2026-66142 Apache Neethi: Uncontrolled recursion in policy processing
- CVE-2026-66143 Apache Neethi: Missing global alternative-output budget across policy computation paths
Sources
Also known as GHSA-q84r-gp7c-vfr3.