What is CVE-2020-13920?

CVE-2020-13920 is a medium-severity vulnerability in Apache Activemq, classified under Missing Authentication for Critical Function. CVSS score: 5.9/10. Published 2020-09-10.

How severe is CVE-2020-13920?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Is CVE-2020-13920 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Apache Activemq

CVE-2020-13920

Apache ActiveMQ uses LocateRegistry.createRegistry() to create the JMX RMI registry and binds the server to the "jmxrmi" entry. It is possible to connect to the registry without authentication and call the rebind method to rebind jmxrmi to something else. If an attacker creates another server to proxy the original, and bound that, he effectively becomes a man in the middle and is able to intercept the credentials when an user connects. Upgrade to Apache ActiveMQ 5.15.12.

Vulnerability class: Broken Authentication

Published 2020-09-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.045 (91.3th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 91st percentile — 91.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.045 · newest: 0.045 · change: 0.000

Affected products

Apache Activemq
Oracle Communications Diameter Signaling Router
Oracle Flexcube Private Banking — versions 12.0.0, 12.1.0
Debian Linux — versions 9.0
Apache Activemq — versions Apache ActiveMQ version prior to 5.15.12

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

Public proof-of-concept exploits

References

activemq.apache.org/security-advisories.data/CVE-2020-13920-announcement.txt (Vendor Advisory)
lists.debian.org/debian-lts-announce/2020/10/msg00013.html (mailing-list, Mailing List, Third Party Advisory)
www.oracle.com/security-alerts/cpuoct2020.html (Third Party Advisory)
lists.apache.org/thread.html/rb2fd3bf2dce042e0ab3f3c94c4767c96bb2e7e6737624d631… (mailing-list)
lists.apache.org/thread.html/r946488fb942fd35c6a6e0359f52504a558ed438574a8f14d3… (mailing-list)
lists.debian.org/debian-lts-announce/2023/11/msg00013.html (mailing-list)

Frequently asked questions

What is CVE-2020-13920?: CVE-2020-13920 is a medium-severity vulnerability in Apache Activemq, classified under Missing Authentication for Critical Function. CVSS score: 5.9/10. Published 2020-09-10.
How severe is CVE-2020-13920?: Medium severity. CVSS v3 base score is 5.9 out of 10.
Is CVE-2020-13920 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.