CVE-2026-91865Hinoki check available

Service interruption via exponential policy-reference re-expansion

Published Sep 21, 2026 · Updated Sep 21, 2026

Resource exhaustion in Apache Neethi before 3.2.4 allows attackers to interrupt an embedding service via a crafted WS-Policy document. The normalization path repeatedly expands sibling references in a policy-reference DAG after its on-path cycle marker is removed, causing work to grow exponentially. Exposure requires an embedding application to normalize attacker-controlled policy input; the resulting CPU and memory exhaustion can hang or crash that application.

CVSS severityUnavailable
Unscored
EPSS probability0.74%
Next 30 days · Oct 20, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Resource exhaustion in Apache Neethi before 3.2.4 allows attackers to interrupt an embedding service via a crafted WS-Policy document. The normalization path repeatedly expands sibling references in a policy-reference DAG after its on-path cycle marker is removed, causing work to grow exponentially. Exposure requires an embedding application to normalize attacker-controlled policy input; the resulting CPU and memory exhaustion can hang or crash that application.

The record

CVE
CVE-2026-91865
Published
Sep 21, 2026
Updated
Sep 21, 2026
Vendor
The Apache Software Foundation
Product
Apache Neethi
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.2.4

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Apache Software Foundation · Apache Neethiversion=0 <3.2.4

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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