9.1

CVE-2021-23128: joomla! project joomla! cms

CVSS: 9.1v3.1CriticalModified
Published 04-03-2021Last modified 25-02-2026
Open JSON

Vulnerability summary

CVE-2021-23128 is a critical (CVSS 9.1) vulnerability in joomla! project joomla! cms. EPSS estimates a 1.38% chance of exploitation in the next 30 days, higher than 71.8% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
1.38%
0%100%
Low · +0.05 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 04-03-2021
    PublishedVulnerability first disclosed.
  2. 25-02-2026
    Last modifiedVulnerability information updated.

Description

An issue was discovered in Joomla! 3.2.0 through 3.9.24. The core shipped but unused randval implementation within FOF (FOFEncryptRandval) used an potential insecure implemetation. That has now been replaced with a call to 'random_bytes()' and its backport that is shipped within random_compat.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

1.38%

Chance of exploitation in the next 30 days

Percentile

72%

Versus all other CVEs

30-day change

+0.05 pp

From 1.33% on 21-09-2026

21-09-202621-10-2026
EPSS score
1.38%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Joomla1 product
Joomla! project1 product

2 vendors · 2 products

References

1 links