CVE-2024-43407: ckeditor XSS — Fix

Description

CKEditor4 is an open source what-you-see-is-what-you-get HTML editor. A potential vulnerability has been discovered in CKEditor 4 Code Snippet GeSHi plugin. The vulnerability allowed a reflected XSS attack by exploiting a flaw in the GeSHi syntax highlighter library hosted by the victim. The GeSHi library was included as a vendor dependency in CKEditor 4 source files. In a specific scenario, an attacker could craft a malicious script that could be executed by sending a request to the GeSHi library hosted on a PHP web server. The GeSHi library is no longer actively maintained. Due to the lack of ongoing support and updates, potential security vulnerabilities have been identified with its continued use. To mitigate these risks and enhance the overall security of the CKEditor 4, we have decided to completely remove the GeSHi library as a dependency. This change aims to maintain a secure environment and reduce the risk of any security incidents related to outdated or unsupported software. The fix is be available in version 4.25.0-lts.

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CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
ckeditor	ckeditor	4.0 — 4.25.0

References

Advisories & Patches

https://github.com/ckeditor/ckeditor4/commit/71072c9f7f263329841bd38e7e5309074c82ef94 https://github.com/ckeditor/ckeditor4/commit/951e7d75fcbcaa2590b0719fb0bb0dd0539ca6fa https://github.com/ckeditor/ckeditor4/security/advisories/GHSA-7r32-vfj5-c2jv

Frequently Asked Questions

What is CVE-2024-43407? +

CKEditor4 is an open source what-you-see-is-what-you-get HTML editor. A potential vulnerability has been discovered in CKEditor 4 Code Snippet GeSHi plugin. The vulnerability allowed a reflected XSS attack by exploiting a flaw in the GeSHi syntax highlighter library hosted by the victim. The GeSHi library was included as a vendor dependency in CKEditor 4 source files. In a specific scenario, an attacker could craft a malicious script that could be executed by sending a request to the GeSHi library hosted on a PHP web server. The GeSHi library is no longer actively maintained. Due to the lack of ongoing support and updates, potential security vulnerabilities have been identified with its continued use. To mitigate these risks and enhance the overall security of the CKEditor 4, we have decided to completely remove the GeSHi library as a dependency. This change aims to maintain a secure environment and reduce the risk of any security incidents related to outdated or unsupported software. The fix is be available in version 4.25.0-lts. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2024-43407? +

CVE-2024-43407 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-43407? +

CVE-2024-43407 affects products from ckeditor, specifically: ckeditor. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-43407? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2024-43407