What is CVE-2021-23123?

CVE-2021-23123 is a medium-severity vulnerability in Joomla Joomla\!, classified under Missing Authorization. CVSS score: 5.3/10. Published 2021-01-12.

How severe is CVE-2021-23123?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Is CVE-2021-23123 known to be exploited?

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

Auth bypass in Joomla Joomla\!

CVE-2021-23123

An issue was discovered in Joomla! 3.0.0 through 3.9.23. The lack of ACL checks in the orderPosition endpoint of com_modules leak names of unpublished and/or inaccessible modules.

Vulnerability class: Broken Access Control

Published 2021-01-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.012 (66.1th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

Joomla Joomla\!
Joomla! Project Cms — versions 3.0.0-3.9.23

Weakness classification (CWE)

CWE-862 — Missing Authorization

Public proof-of-concept exploits

CyberCommands/CVE2021-23132

References

developer.joomla.org/security-centre/836-20210101-core-com-modules-exposes-modu… (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2021-23123?: CVE-2021-23123 is a medium-severity vulnerability in Joomla Joomla\!, classified under Missing Authorization. CVSS score: 5.3/10. Published 2021-01-12.
How severe is CVE-2021-23123?: Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2021-23123 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.