CVE-2026-91865 Apache CVE debrief

Who should care

Apache Neethi users and administrators should assess exposure and upgrade to version 3.2.4 to prevent denial of service attacks. This includes operators managing Neethi deployments, platform administrators, vulnerability management teams, and security teams responsible for monitoring and protecting against potential system crashes or freezes due to excessive CPU and memory consumption. Security teams should review compensating controls for exposed systems,

Why it matters

CVE-2026-91865 is a high-severity vulnerability in Apache Neethi that can cause denial of service attacks. Users should upgrade to version 3.2.4 to prevent potential system crashes or freezes.

• Denial of service due to excessive CPU and memory consumption
• Potential system crashes or freezes
• Need for urgent upgrade to version 3.2.4

Technical summary

A small WS-Policy document using repeated policy references can force Neethi to re-expand the same references exponentially during normalization, consuming huge amounts of CPU and memory (denial of service). This occurs in Apache Neethi, a WS-Policy document processor. The vulnerability has a CVSS score of 7.5 and is considered high severity. Users are recommended to upgrade to version 3.2.4, which fixes this issue. The vulnerability is triggered by specially crafted WS-Policy documents with repeated policy references.

Defensive priority

Upgrade to version 3.2.4 to prevent denial of service attacks

Recommended defensive actions

• Upgrade Apache Neethi to version 3.2.4
• Review and update WS-Policy document processing to prevent excessive CPU and memory consumption
• Monitor Apache Neethi systems for potential denial of service attacks
• Confirm whether affected Apache Neethi deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The vulnerability is described in the CVE record and NVD vulnerability detail page. Apache has provided a fix in version 3.2.4. Evidence limits are based on CVE and NVD details. Defenders should verify affected Apache Neethi deployments and upgrade to version 3.2.4. Limited source detail suggests additional verification may be needed for full exposure assessment.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.