What is CVE-2026-67589?

CVE-2026-67589 is a high-severity vulnerability in Apache Qpid Protonj2, classified under CWE-789. CVSS score: 7.5/10. Published 2026-08-05.

How severe is CVE-2026-67589?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Apache Qpid Protonj2

CVE-2026-67589

A pre-authentication attacker could leverage type size/count handling to cause excessive allocation leading to potential 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.

Published 2026-08-05 · last modified 2026-10-24.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.008 (55.8th percentile), scored 2026-11-04.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 55.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Apache Qpid Protonj2
Apache Software Foundation Qpid Protonj2 — versions 0

Weakness classification (CWE)

CWE-789

References

lists.apache.org/thread/bs24x4778dh72xtfs299cy8krvdlo47q (vendor-advisory, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)

Frequently asked questions

What is CVE-2026-67589?: CVE-2026-67589 is a high-severity vulnerability in Apache Qpid Protonj2, classified under CWE-789. CVSS score: 7.5/10. Published 2026-08-05.
How severe is CVE-2026-67589?: High severity. CVSS v3 base score is 7.5 out of 10.