CVE-2021-33829: XSS

Published May 25, 2021
·
Updated

A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript code through a crafted comment because --!> is mishandled.

Other sources

A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript code through a crafted comment because --!> is mishandled.

CKEditor is vulnerable to cross-site scripting, caused by improper validation of user-supplied input. A remote attacker could exploit this vulnerability to inject malicious script into a Web page which would be executed in a victim's Web browser within the security context of the hosting Web site, once the page is viewed. An attacker could use this vulnerability to steal the victim's cookie-based authentication credentials.

Drupal core - Critical - Cross-site scripting - SA-CORE-2021-003

Affected Software

19 affected componentsFixes available
composer/drupal/drupal>=7.0.0, <7.80, >=8.0.0, <8.1.0, >=8.1.0, <8.2.0, >=8.2.0, <8.3.0, >=8.3.0, <8.4.0, >=8.4.0, <8.5.0, >=8.5.0, <8.6.0, >=8.6.0, <8.7.0, >=8.7.0, <8.8.0, >=8.8.0, <8.9.0, >=8.9.0, <8.9.16, >=9.0.0, <9.0.14, >=9.1.0, <9.1.9
composer/drupal/core>=7.0.0, <7.80, >=8.0.0, <8.1.0, >=8.1.0, <8.2.0, >=8.2.0, <8.3.0, >=8.3.0, <8.4.0, >=8.4.0, <8.5.0, >=8.5.0, <8.6.0, >=8.6.0, <8.7.0, >=8.7.0, <8.8.0, >=8.8.0, <8.9.0, >=8.9.0, <8.9.16, >=9.0.0, <9.0.14, >=9.1.0, <9.1.9
composer/drupal/drupal>=9.1.0<9.1.9
9.1.9
composer/drupal/drupal>=9.0.0<9.0.14
9.0.14
composer/drupal/drupal>=8.0.0<8.9.16
8.9.16
composer/drupal/drupal>=7.0.0<7.80
7.80
composer/drupal/core>=9.1.0<9.1.9
9.1.9
composer/drupal/core>=9.0.0<9.0.14
9.0.14
composer/drupal/core>=8.0.0<8.9.16
8.9.16
composer/drupal/core>=7.0.0<7.80
7.80
npm/ckeditor4>=4.14.0<4.16.1
4.16.1
CKEditor CKEditor>=4.14.0<4.16.1
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Fedoraproject Fedora=35
Drupal Drupal>=8.9.0<8.9.16
Drupal Drupal>=9.0.0<9.0.14
Drupal Drupal>=9.1.0<9.1.9
Debian Debian Linux=9.0

Event History

May 25, 2021
Advisory Published
06:02 PM
Jun 9, 2021
CVE Published
via MITRE·11:51 AM
Data Sourced
via MITRE·11:51 AM
Description
Aug 3, 2024
Data Sourced
via IBM·05:47 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-33829?

CVE-2021-33829 is a vulnerability in Drupal core that allows for cross-site scripting (XSS) attacks.

2

How severe is CVE-2021-33829?

CVE-2021-33829 has a severity rating of 7.2, which is considered high.

3

How does CVE-2021-33829 affect Drupal websites?

CVE-2021-33829 can allow remote attackers to inject malicious scripts into a Drupal website, which can be executed by visitors to the site, compromising their browsing security.

4

What versions of Drupal are affected by CVE-2021-33829?

Versions 7.x, 8.x, and 9.x of Drupal are affected by CVE-2021-33829.

5

Where can I find more information about CVE-2021-33829 and its remediation?

For more information about CVE-2021-33829 and its remediation, you can visit the Drupal Security Advisory SA-CORE-2021-003 or the IBM X-Force Exchange website.

Contact

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