CVE-2026-42403Network attack vector

Unauthenticated hang via circular policy reference recursion

Published May 1, 2026 · Updated May 1, 2026

Uncontrolled recursion in Apache Neethi before 3.2.2 allows remote attackers to hang applications via circular WS-Policy references. The policy normalization process repeatedly resolves Policy A to Policy B and back to Policy A without detecting the cycle, causing infinite iteration or stack exhaustion. Exposure requires a consuming application to pass attacker-controlled WS-Policy documents to Neethi, and the bounded consequence is a stack overflow or application hang.

CVSS severity7.5
High
EPSS probability0.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled recursion in Apache Neethi before 3.2.2 allows remote attackers to hang applications via circular WS-Policy references. The policy normalization process repeatedly resolves Policy A to Policy B and back to Policy A without detecting the cycle, causing infinite iteration or stack exhaustion. Exposure requires a consuming application to pass attacker-controlled WS-Policy documents to Neethi, and the bounded consequence is a stack overflow or application hang.

The record

CVE
CVE-2026-42403
Published
May 1, 2026
Updated
May 1, 2026
Vendor
The Apache Software Foundation
Product
Apache Neethi
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 1, 2026CVE publishedPublication date reported by the CVE source.
  2. May 1, 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?

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  1. Affected versionversion=0 <3.2.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Neethiversion=0 <3.2.2

Published CVSS scores

7.5Apache Software FoundationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
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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Your stack

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