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Fencer Vulns
high 7.5

CVE-2026-66257 json

Apache Qpid Proton-J: Unbounded symbol value caching can lead to pre-authentication resource exhaustion

published 2026-08-05 3 mo ago modified 2026-10-24 16 d ago also EUVD-2026-53051

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 56%
public exploits
0
none known

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 Proton-J: through 0.34.1.

Users are recommended to upgrade to version 0.35.0, which fixes the issue.

Patch / fix

  • apache qpid_proton-j 0.35.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-66257 updated cvss 7.5

qpid-proton-j: Apache Qpid Proton-J: Denial of Service via unbounded symbol value caching

  • Red Hat build of Apache Camel 4 for Quarkus 3 proton-j Red Hat JBoss Enterprise Application Platform Expansion Pack proton-j
    affected: workaround, no fix available
  • Red Hat AMQ Clients 2026.Q3
    fixed: vendor fix RHSA-2026:69459
  • Red Hat AMQ Broker 7.13.6
    fixed: vendor fix RHSA-2026:66545
  • Red Hat AMQ Broker 7.14.1
    fixed: vendor fix RHSA-2026:66488
  • Red Hat Build of Apache Camel 3.33.3.SP1 proton-j 0.35.0.redhat-00001
    fixed: vendor fix RHSA-2026:63302
  • Red Hat build of Apache Camel 4.18.4 for Spring Boot 3.5.16
    fixed: vendor fix RHSA-2026:71675
  • Red Hat build of Quarkus 3.27.5.SP1 proton-j 0.35.0.redhat-00001
    fixed: vendor fix RHSA-2026:62515
  • Red Hat build of Quarkus 3.33.3.SP1 proton-j 0.35.0.redhat-00001
    fixed: vendor fix RHSA-2026:62555
show 3 more
  • Red Hat JBoss Enterprise Application Platform 8.1
    fixed: vendor fix RHSA-2026:95221
  • Red Hat Build of Apache Camel 3.33.3.SP1 jimfs 1.1, jna 5.8.0, bcel 6.7.0, gax 2.74.1, icu4j 78.2, joni 2.2.6, +1618 more Red Hat build of Quarkus 3.27.5.SP1 jna 5.8.0, db2 1.21.4, h2 2.3.230, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, +1009 more Red Hat build of Quarkus 3.33.3.SP1 jna 5.8.0, h2 2.4.240, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, wasm 2.15.3, +1018 more
    not affected: vulnerable code not present
  • Red Hat JBoss Enterprise Application Platform 8 proton-j
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.77% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Apache Software Foundation Apache Qpid Proton-J

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.