CVE-2025-15129 identifies a code injection vulnerability in the ChenJinchuang Lin-CMS-TP5 content management system, affecting versions 0.3.0 through 0.3.3. The vulnerability resides in the Upload function within the file application/lib/file/LocalUploader.php, part of the File Upload Handler component. An attacker can remotely manipulate the 'File' argument passed to this function to inject malicious code, which the system may execute, leading to unauthorized code execution on the server. This flaw does not require authentication or user interaction, making it exploitable over the network by any remote attacker. The vulnerability was responsibly disclosed via an issue report, but the vendor has not issued a patch or response as of the publication date (December 28, 2025). A public exploit has been published, increasing the likelihood of active exploitation attempts. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and low impacts on confidentiality, integrity, and availability (VC:L, VI:L, VA:L). The vulnerability affects the confidentiality, integrity, and availability of affected systems by enabling arbitrary code execution, potentially leading to full system compromise. The lack of vendor patch and the availability of exploits make this a significant risk for organizations using this CMS, especially those hosting public-facing web applications.

For European organizations using Lin-CMS-TP5, this vulnerability poses a risk of unauthorized remote code execution, potentially leading to data breaches, defacement, or complete system takeover. The impact includes loss of confidentiality due to data exposure, integrity violations through unauthorized code execution, and availability disruptions if attackers deploy destructive payloads or ransomware. Organizations relying on Lin-CMS-TP5 for critical web services or internal applications may face operational disruptions and reputational damage. Given the public exploit availability and lack of vendor patch, attackers may rapidly target vulnerable systems. The medium CVSS score reflects moderate impact but ease of exploitation without authentication increases urgency. European entities in sectors such as government, education, and SMEs using this CMS are particularly vulnerable. The threat also extends to supply chain risks if compromised systems serve as pivot points for broader network infiltration.

1. Immediately implement strict input validation and sanitization on all file upload parameters, especially the 'File' argument in the Upload function, to prevent code injection. 2. Temporarily disable or restrict file upload functionality in Lin-CMS-TP5 installations until a vendor patch is released. 3. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious file upload attempts targeting this vulnerability. 4. Monitor server logs and network traffic for unusual activity indicative of exploitation attempts, such as unexpected file uploads or execution of unauthorized scripts. 5. Isolate affected systems from critical networks to limit potential lateral movement if compromise occurs. 6. Consider migrating to alternative, actively maintained CMS platforms with robust security support. 7. Maintain regular backups of affected systems and verify their integrity to enable recovery in case of compromise. 8. Engage with the vendor or community to track patch developments and apply updates promptly once available. 9. Conduct security awareness training for administrators to recognize and respond to exploitation signs. 10. Use intrusion detection systems (IDS) to alert on anomalous behaviors related to file uploads and code execution.