The vulnerability CVE-2026-57801 affects Select-Themes SetSail through version 2.1 and is caused by improper validation or control of filenames used in PHP include or require statements. This improper control allows an attacker to perform Local File Inclusion (LFI), which can lead to arbitrary code execution or unauthorized file access. The CVSS 3.1 vector indicates network attack vector, high attack complexity, low privileges required, no user interaction, unchanged scope, and high impact on confidentiality, integrity, and availability. No vendor advisory or patch information is provided, and the remediation level is unknown.

Successful exploitation of this vulnerability can lead to full compromise of the affected system, including unauthorized disclosure of sensitive information, modification of data, and disruption of service. The attacker requires only low privileges and no user interaction, but the attack complexity is high. The vulnerability affects confidentiality, integrity, and availability at a high level.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should consider restricting access to vulnerable endpoints, applying web application firewalls with rules to detect and block LFI attempts, and reviewing PHP configuration to disable potentially dangerous functions if feasible. Monitor vendor channels for updates and patches.