CVE-2021-26035

[20210701] - Core - XSS in JForm Rules field

Description

An issue was discovered in Joomla! 3.0.0 through 3.9.27. Inadequate escaping in the rules field of the JForm API leads to a XSS vulnerability.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 3.54% Top 15%
Vendor Advisory joomla.org
Affected: Joomla! Project Joomla! CMS
Published at:
Updated at:

References

Link Tags
https://developer.joomla.org/security-centre/856-20210701-core-xss-in-jform-rules-field.html vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-26035?
CVE-2021-26035 has been scored as a medium severity vulnerability.
How to fix CVE-2021-26035?
To fix CVE-2021-26035, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-26035 being actively exploited in the wild?
It is possible that CVE-2021-26035 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~4% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-26035?
CVE-2021-26035 affects Joomla! Project Joomla! CMS.
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