GetSimpleCMS-CE GetSimple CMS up to 1.4 Update Form upgrade.json url cross-site request forgery

Summaryinfo

A vulnerability was found in GetSimpleCMS-CE GetSimple CMS up to 1.4. It has been declared as problematic. Affected is an unknown function of the file upgrade.json of the component Update Form. Such manipulation of the argument url leads to cross-site request forgery. This vulnerability is documented as CVE-2026-56662. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in GetSimpleCMS-CE GetSimple CMS up to 1.4. Affected by this issue is some unknown processing of the file upgrade.json of the component Update Form. The manipulation of the argument url with an unknown input leads to a cross-site request forgery vulnerability. Using CWE to declare the problem leads to CWE-352. The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request. Impacted is integrity. CVE summarizes:

GetSimple CMS is a content management system (CMS), and GetSimple CMS CE is the community edition of that CMS. Prior to version 1.5, the UpdateCE update form contained no anti-CSRF token, and the POST handler performed no token or request-origin verification. A remote attacker can host a page that auto-submits a forged POST to the update endpoint; when an authenticated administrator visits it, the server performs an attacker-directed download-and-deploy operation in the administrator's session — with no further interaction. Because the deployed content is executed (see the related ZIP-extraction advisory), this yields remote code execution. The url field is additionally written into the form unescaped, providing a secondary HTML-injection sink via a malicious upgrade.json. This issue has been patched in version 1.5.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-56662 since 06/22/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

By approaching the search of inurl:upgrade.json it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 1.5 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Content Management System

Vendor

• GetSimpleCMS-CE

Name

• GetSimple CMS

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4

License

• free

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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