CVE-2021-26035 - Vulnerability Details - OpenCVE

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.

Published: 2021-07-07

Score: 6.1 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Joomla! Project

Joomla! CMS

affected

Version	Status	Constraints
`3.0.0-3.9.27`	affected	—

Configuration 1 [-]

cpe:2.3:a:joomla:joomla\!:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-12858	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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00723.

Key SSVC decision points have not yet been added.

References

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

History

No history.

Subscriptions

Joomla Joomla\!

MITRE

Status: PUBLISHED

Assigner: Joomla

Published: 2021-07-07T10:12:45.054Z

Updated: 2026-02-25T05:05:49.340Z

Reserved: 2021-01-25T00:00:00.000Z

Link: CVE-2021-26035

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-07-07T11:15:08.603

Modified: 2026-06-17T03:42:46.557

Link: CVE-2021-26035

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-79
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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