What is CVE-2021-26034?

CVE-2021-26034 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2021-05-26.

How severe is CVE-2021-26034?

Medium severity. CVSS v3 base score is 6.5 out of 10.

CSRF in Joomla Joomla\!

CVE-2021-26034

An issue was discovered in Joomla! 3.0.0 through 3.9.26. A missing token check causes a CSRF vulnerability in data download endpoints in com_banners and com_sysinfo.

Vulnerability class: CSRF (Cross-Site Request Forgery)

Published 2021-05-26 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (40.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 40.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Joomla Joomla\!
Joomla! Project Cms — versions 3.0.0-3.9.26

Weakness classification (CWE)

CWE-352 — Cross-Site Request Forgery (CSRF)

References

developer.joomla.org/security-centre/854-20210503-core-csrf-in-data-download-en… (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2021-26034?: CVE-2021-26034 is a medium-severity vulnerability in Joomla Joomla\!, classified under Cross-Site Request Forgery (CSRF). CVSS score: 6.5/10. Published 2021-05-26.
How severe is CVE-2021-26034?: Medium severity. CVSS v3 base score is 6.5 out of 10.