apostrophe up to 4.28.x Meta Description cross site scripting

Summaryinfo

A vulnerability, which was classified as problematic, was found in apostrophe up to 4.28.x. Affected by this issue is some unknown functionality of the component Meta Description Handler. Such manipulation leads to cross site scripting. This vulnerability is uniquely identified as CVE-2026-35569. The attack can be launched remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in apostrophe up to 4.28.x. Affected by this issue is some unknown functionality of the component Meta Description Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

ApostropheCMS is an open-source Node.js content management system. Versions 4.28.0 and prior contain a stored cross-site scripting vulnerability in SEO-related fields (SEO Title and Meta Description), where user-controlled input is rendered without proper output encoding into HTML contexts including tags, attributes, and JSON-LD structured data. An attacker can inject a payload such as ">alert(1) to break out of the intended HTML context and execute arbitrary JavaScript in the browser of any authenticated user who views the affected page. This can be leveraged to perform authenticated API requests, access sensitive data such as usernames, email addresses, and roles via internal APIs, and exfiltrate it to an attacker-controlled server. This issue has been fixed in version 4.29.0.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-35569 since 04/03/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

Upgrading to version 4.29.0 eliminates this vulnerability. Applying the patch 0e57dd07a56ae1ba1e3af646ba026db4d0ab5bb3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• apostrophe

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28

License

• open-source

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• 🔒
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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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