Release Date: May 20, 2025Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.Component: "Front End User Registration" (sr_feuser_register)Composer Package Name: sjbr/sr-feuser-registerVulnerability Type: Remote Code Execution and Insecure Direct Object ReferenceAffected Versions: 5.1.0 – 12.4.8Severity: CriticalSuggested CVSS v3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:CReferences: CVE-2025-48200, CVE-2025-48205, CWE-502, CWE-639 Problem Description The extension allows the exchange of a serialized file object representation of a previously uploaded file without proper validation. This enables an attacker to inject arbitrary serialized PHP objects, which may be deserialized on the server side, potentially leading to Remote Code Execution (RCE). The extension does not verify if a specified file identifier is authorized for download. This allows an attacker to disclose and download arbitrary files without further authentication, resulting in an Insecure Direct Object Reference (IDOR) vulnerability. Solution An updated version 12.5.0 is available from the TYPO3 extension manager, packagist and athttps://extensions.typo3.org/extension/download/sr_feuser_register/12.5.0/zip Users of the extension are advised to update the extension as soon as possible. Credits Thanks to Johannes Seipelt for reporting the RCE vulnerability, to Security Team Member Torben Hansen for reporting the IDOR issue, and to Stanislas Roland for providing updated versions of the extension. General Advice Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.