CVE-2021-26036

mediumpriority · track · 30EPSS 0.012 · 69 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.22% (69th) EPSS

CVSS 5 · medium

Is it mine?

3 products

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

An issue was discovered in Joomla! 2.5.0 through 3.9.27. Missing validation of input could lead to a broken usergroups table.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

BIT-joomla-2021-26036[20210702] - Core - DoS through usergroup table manipulation2025-04-03vendor · osvUS
An issue was discovered in Joomla! 2.5.0 through 3.9.27. Missing validation of input could lead to a broken usergroups table.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-07-07modified 2026-06-17

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External citations — patches, advisories, analysis.

scry

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