CVE-2026-66257
Received Received - Intake

Denial of Service in Apache Qpid Proton-J via Symbol Value Caching

Publication date: 2026-08-05

Last updated on: 2026-08-05

Assigner: Apache Software Foundation

Description
A pre-authentication attacker could leverage unbounded symbol value caching to cause resource exhaustion leading to denial of service. This issue affects Apache Qpid Proton-J: through 0.34.1. Users are recommended to upgrade to version 0.35.0, which fixes the issue.

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Meta Information

Published
2026-08-05
Last Modified
2026-08-05
Generated
2026-08-05
AI Q&A
2026-08-05
EPSS Evaluated
N/A
NVD
CVE-2026-66257
EUVD
EUVD-2026-53051

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
apache qpid_proton_j to 0.35.0 (exc)

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Exploitability

CWE
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KEV
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CWE ID Description
CWE-770 The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

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Executive Summary

This vulnerability allows an attacker to cause a denial of service by exploiting unbounded symbol value caching before authentication. It affects Apache Qpid Proton-J versions up to 0.34.1.

Detection Guidance

Detection involves checking the Apache Qpid Proton-J version in use. Commands like 'qpid-proton-j --version' or inspecting application dependencies can help identify vulnerable versions (through 0.34.1).

Monitor for resource exhaustion symptoms such as high CPU/memory usage or service crashes, which may indicate exploitation attempts.

Impact Analysis

An attacker could exploit this to exhaust system resources, leading to service disruption or crashes. Systems using vulnerable versions of Apache Qpid Proton-J are at risk.

Mitigation Strategies

Upgrade Apache Qpid Proton-J to version 0.35.0 or later immediately to address the vulnerability.

Apply network-level protections to limit pre-authentication access to vulnerable services until patched.

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