---
id: CVE-2026-67588
title: >-
  A pre-authentication attacker could leverage unbounded symbol value caching to
  cause resource exhaustion leading to denial of service.


  This issue affects Apache Qpid ProtonJ2: through 1.1.0.


  Users are recommended to upgrade to version …
summary: >-
  A pre-authentication attacker could leverage unbounded symbol value caching to
  cause resource exhaustion leading to denial of service.


  This issue affects Apache Qpid ProtonJ2: through 1.1.0.


  Users are recommended to upgrade to version …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-770
vendor: apache
product: qpid_protonj2
affected:
  - qpid_protonj2 < 1.2.0
patched:
  - qpid_protonj2 1.2.0
published: '2026-08-05'
updated: '2026-08-07'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67588'
references:
  - url: 'https://lists.apache.org/thread/vk4j02dzggfdrdkwvzmqo4jro2tgj0jt'
    label: security@apache.org
  - url: 'http://www.openwall.com/lists/oss-security/2026/08/04/27'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67588.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-67588'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2511324'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-67588'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67588'
  - url: 'https://access.redhat.com/errata/RHSA-2026:69459'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00774
epssPercentile: 0.53869
ingestedAt: '2026-08-08T20:29:48.994Z'
---

## Overview

A pre-authentication attacker could leverage unbounded symbol value caching to cause resource exhaustion leading to denial of service.

This issue affects Apache Qpid ProtonJ2: through 1.1.0.

Users are recommended to upgrade to version 1.2.0, which fixes the issue.

## Affected

- `qpid_protonj2 < 1.2.0`

## Remediation

Upgrade past the affected range:

- `qpid_protonj2 1.2.0`

## Vendor advisories

- **RHSA-2026:69459** · Red Hat · fixed in: AMQ Clients 2026.Q3 · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69459)