CVE-2025-53335 is a remote file inclusion (RFI) vulnerability found in the ThemeREX Berger PHP theme, specifically affecting versions up to 1.1.1. The root cause is improper control of filenames used in PHP include or require statements, which allows an attacker to manipulate the file path and include arbitrary remote files. This can lead to remote code execution (RCE), enabling attackers to run malicious code on the server hosting the vulnerable theme. The vulnerability does not require authentication or user interaction, but the attack complexity is rated high, indicating some conditions must be met for successful exploitation. The CVSS v3.1 base score is 8.1, reflecting high impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the vulnerability poses a serious risk to websites using the affected theme, potentially allowing attackers to compromise sensitive data, deface websites, or disrupt services. The issue was reserved in June 2025 and published in March 2026, with no official patches currently linked, emphasizing the need for immediate mitigation efforts by users of the Berger theme.

The vulnerability allows attackers to execute arbitrary code remotely, which can lead to full system compromise. This impacts confidentiality by exposing sensitive data, integrity by allowing unauthorized modifications, and availability by potentially causing service disruptions or denial of service. Organizations running websites with the affected ThemeREX Berger theme are at risk of data breaches, website defacement, malware distribution, and loss of customer trust. The lack of authentication requirement and no need for user interaction increase the attack surface, making automated exploitation feasible once a reliable exploit is developed. The high attack complexity somewhat limits mass exploitation but does not eliminate targeted attacks. The absence of known exploits in the wild currently reduces immediate risk but should not lead to complacency. Overall, the threat is significant for organizations relying on this theme, especially those handling sensitive or critical data.

1. Immediately update the ThemeREX Berger theme to a patched version once available from the vendor. 2. In the absence of an official patch, disable or restrict the use of dynamic include/require statements in the theme’s PHP code by applying manual code reviews and hardening. 3. Implement web application firewalls (WAF) with rules to detect and block suspicious file inclusion attempts, especially those containing remote URLs or unexpected parameters. 4. Restrict PHP configurations such as allow_url_include=Off and disable dangerous PHP functions like include, require, and file_get_contents for untrusted inputs. 5. Conduct regular security audits and vulnerability scans focusing on PHP applications and themes. 6. Monitor web server logs for unusual requests that may indicate exploitation attempts. 7. Employ least privilege principles for web server file permissions to limit damage if exploitation occurs. 8. Educate developers and administrators about secure coding practices to prevent similar vulnerabilities in custom themes or plugins.