The vulnerability identified as CVE-2026-27745 affects the SPIP content management system's interface_traduction_objets plugin versions prior to 4.3.3. It is classified under CWE-94, indicating improper control of code generation or code injection. The core issue stems from the plugin's handling of untrusted input data within the translation interface workflow. Specifically, the plugin incorporates untrusted request data into a hidden form field that is rendered without SPIP's standard output filtering. Additionally, fields prefixed with an underscore bypass SPIP's protection mechanisms, allowing this hidden content to be rendered with filtering disabled. An attacker who is authenticated with editor-level privileges can craft malicious input that is injected into this hidden field. This injected content is then processed and evaluated by SPIP's template engine, resulting in remote code execution within the context of the web server. The vulnerability does not require user interaction and can be exploited remotely over the network. The CVSS 4.0 base score is 8.7, reflecting high severity due to the ease of exploitation (network attack vector, low attack complexity, no user interaction), the requirement for privileges (editor-level), and the high impact on confidentiality, integrity, and availability. Although no known exploits are reported in the wild, the vulnerability poses a significant risk to SPIP users until patched. No official patch links were provided at the time of this report, but upgrading to version 4.3.3 or later is implied as the remediation path.

If exploited, this vulnerability allows an attacker with editor-level access to execute arbitrary code on the web server hosting the SPIP CMS. This can lead to full compromise of the affected system, including unauthorized data access, data modification, service disruption, and potential lateral movement within the network. The confidentiality of sensitive content managed by SPIP can be breached, integrity of website content and configurations can be altered, and availability can be impacted through denial-of-service or destructive payloads. Organizations relying on SPIP for content management, especially those with multiple editors or contributors, face elevated risk since any compromised editor account can be leveraged for exploitation. The vulnerability's remote exploitation capability increases the attack surface, potentially allowing attackers to bypass perimeter defenses once editor credentials are obtained. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, as public disclosure may prompt attackers to develop exploits rapidly.

Organizations should immediately upgrade the interface_traduction_objets plugin to version 4.3.3 or later, where this vulnerability is addressed. If upgrading is not immediately feasible, restrict editor-level privileges to trusted users only and implement strict access controls and monitoring on accounts with such privileges. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious payloads targeting the translation interface workflow, especially those attempting to inject code via hidden form fields. Review and harden SPIP template processing configurations to enforce output filtering and disable or restrict processing of fields prefixed with underscores. Conduct regular audits of editor activity logs to detect anomalous behavior indicative of exploitation attempts. Additionally, consider network segmentation to limit exposure of the SPIP server and employ multi-factor authentication to reduce the risk of credential compromise. Finally, monitor vulnerability advisories and threat intelligence feeds for updates or emerging exploit reports related to this CVE.