CVE-2026-1311 is a path traversal vulnerability classified under CWE-22 found in the Worry Proof Backup plugin for WordPress, versions up to and including 0.2.4. The vulnerability arises from improper validation of pathname inputs during the backup upload process. Authenticated attackers with at least Subscriber-level privileges can upload a malicious ZIP archive containing path traversal sequences (e.g., '../') that bypass directory restrictions. This allows them to write arbitrary files to any location on the server's filesystem, including web-accessible directories. By placing executable PHP files, attackers can achieve remote code execution (RCE), gaining full control over the affected server. The vulnerability does not require user interaction beyond authentication and has a low attack complexity with no special privileges beyond Subscriber access. The CVSS v3.1 score of 8.8 reflects the high impact on confidentiality, integrity, and availability, as attackers can exfiltrate data, modify or delete files, and disrupt services. Although no known exploits have been reported in the wild, the vulnerability poses a significant risk due to the widespread use of WordPress and the plugin's functionality. The lack of available patches at the time of reporting necessitates immediate mitigation efforts by administrators.

The exploitation of CVE-2026-1311 can have severe consequences for organizations running WordPress sites with the vulnerable Worry Proof Backup plugin. Attackers can gain the ability to write arbitrary files anywhere on the server, including uploading web shells or other malicious scripts, leading to full remote code execution. This compromises the confidentiality of sensitive data stored on the server, the integrity of website content and backend systems, and the availability of services due to potential server disruption or defacement. The breach can facilitate further lateral movement within the network, data exfiltration, and persistent access. Organizations relying on WordPress for business-critical applications or e-commerce are particularly at risk, as attackers could manipulate transactions, steal customer data, or deploy ransomware. The vulnerability's low exploitation complexity and minimal privilege requirements increase the likelihood of attacks, especially in environments with weak user access controls or where Subscriber-level accounts are common. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, as public disclosure often leads to rapid development of exploit code.

To mitigate CVE-2026-1311, organizations should immediately assess their WordPress installations for the presence of the Worry Proof Backup plugin and verify the version in use. Since no official patches are available at the time of reporting, administrators should consider temporarily disabling or uninstalling the plugin to eliminate the attack vector. Restricting user roles and permissions is critical; limit Subscriber-level accounts and audit existing users to ensure no unnecessary privileges are granted. Implement web application firewalls (WAFs) with rules to detect and block path traversal patterns in file uploads. Monitor server logs for suspicious upload activity or unexpected file creations, especially PHP files in non-standard directories. Employ file integrity monitoring to detect unauthorized changes. Segregate web server permissions to restrict write access to only necessary directories and disable execution permissions in upload directories. Once a patch or update is released by the vendor, apply it promptly. Additionally, educate users about the risks of granting excessive privileges and enforce strong authentication mechanisms to reduce the risk of compromised accounts.