CVE-2021-26030
Medium3.0.0 through 3.9.25.
Published Apr 14, 2021 · Updated Sep 8, 2026 · Also known as BIT-joomla-2021-26030
Key Facts
Patch immediately- CVE-2021-26030 is a medium-severity vulnerability (CVSS 6.1 v3.1) affecting Joomla\!, joomla (bitnami), Joomla! CMS.
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 82% probability of exploitation in the next 30 days.
- Fixed versions are available, including Joomla\! <=3.9.25, Joomla\! 3.9.25.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
6.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS (30-day exploit likelihood)
82%
Higher than 99.6% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
None known
Get the full CVE-2021-26030 brief as a PDF
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Description
An issue was discovered in Joomla! 3.0.0 through 3.9.25. Inadequate escaping allowed XSS attacks using the logo parameter of the default templates on error page
Affected Products
3 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Joomla\!Joomla | See advisory | 3.9.25 |
| joomlabitnami | >= 3.0.0 | n/a |
| Joomla! CMS | >= 3.0.0-3.9.25 | n/a |
Patched Releases
Joomla\!
<=3.9.25
Timeline
Publicly disclosed
Apr 14, 2021
Last updated
Sep 8, 2026
Weakness Type
- CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
References
FAQ
Common Questions.
An issue was discovered in Joomla!
Affected: Joomla\!; joomla (bitnami) versions >= 3.0.0; Joomla! CMS versions >= 3.0.0-3.9.25. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Joomla\! <=3.9.25, Joomla\! 3.9.25.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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