CVE-2021-35955 - Vulnerability Details - OpenCVE

Description

Contao >=4.0.0 allows backend XSS via HTML attributes to an HTML field. Fixed in 4.4.56, 4.9.18, 4.11.7.

Published: 2021-08-12

Score: 4.8 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

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:contao:contao::::::::
	cpe:2.3:a:contao:contao::::::::
	cpe:2.3:a:contao:contao::::::::

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-2021-1756	Cross site scripting via HTML attributes in the back end
Github GHSA	GHSA-hr3h-x6gq-rqcp	Cross site scripting via HTML attributes in the back end

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required High

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 Single

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00557.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://contao.org/en/news/contao-4-9-16-and-4-11-5-are-available.html
https://github.com/contao/contao/security/advisories/GHSA-hr3h-x6gq-rqcp

History

No history.

Subscriptions

Contao Contao

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-08-12T14:33:44.000Z

Updated: 2024-08-04T00:47:42.583Z

Reserved: 2021-06-29T00:00:00.000Z

Link: CVE-2021-35955

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-08-12T15:15:07.960

Modified: 2026-06-17T03:58:01.780

Link: CVE-2021-35955

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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