CVE-2025-53216 is a high-severity vulnerability classified under CWE-98, which involves improper control of filenames used in include or require statements within PHP programs. Specifically, this vulnerability affects the ThemeUniver Glamer product, versions up to and including 1.0.2. The flaw allows for PHP Local File Inclusion (LFI), meaning an attacker can manipulate the filename parameter used in PHP include or require functions to load unintended files from the local filesystem. This can lead to arbitrary code execution, disclosure of sensitive information, or full system compromise depending on the files included and the context of execution. The vulnerability is remotely exploitable over the network (AV:N), requires no privileges (PR:N), and no user interaction (UI:N), but has a high attack complexity (AC:H), 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. No known exploits are reported in the wild yet, and no patches have been linked at the time of publication. The vulnerability arises from insufficient validation or sanitization of user-supplied input used in PHP include/require statements, a common security weakness in web applications that can be exploited to include arbitrary files, potentially leading to remote code execution or data leakage. Given the nature of PHP applications and the widespread use of themes and plugins, this vulnerability poses a significant risk to websites using the Glamer theme, especially if exposed to the internet without additional protections.

For European organizations, the impact of this vulnerability can be substantial, particularly for those relying on the ThemeUniver Glamer theme in their web infrastructure. Exploitation could lead to unauthorized disclosure of sensitive data, including customer information, internal configuration files, or credentials. Integrity of the affected systems could be compromised through arbitrary code execution, allowing attackers to modify website content, inject malicious scripts, or establish persistent backdoors. Availability may also be affected if attackers disrupt services or cause application crashes. Organizations in sectors such as e-commerce, government, healthcare, and finance, which often handle sensitive personal and financial data, are at increased risk of regulatory penalties under GDPR if data breaches occur. Additionally, reputational damage and operational disruption could result from successful exploitation. Since the vulnerability requires no authentication and no user interaction, any publicly accessible web server running the vulnerable theme is at risk, increasing the attack surface for European entities hosting websites with this theme.

To mitigate this vulnerability, European organizations should first identify any deployments of the ThemeUniver Glamer theme version 1.0.2 or earlier. Immediate steps include: 1) Applying any available patches or updates from ThemeUniver as soon as they are released. 2) If patches are not yet available, implement virtual patching via web application firewalls (WAFs) to block suspicious requests attempting to manipulate include parameters or access unexpected files. 3) Conduct code reviews and harden PHP include/require statements by enforcing strict input validation and sanitization, ensuring only allowed filenames or paths are accepted. 4) Restrict file permissions on the web server to limit access to sensitive files that could be included. 5) Monitor web server logs for anomalous requests indicative of LFI attempts. 6) Employ network segmentation and least privilege principles to limit the impact of a potential compromise. 7) Educate development and operations teams about secure coding practices related to file inclusion vulnerabilities. These targeted measures go beyond generic advice by focusing on the specific nature of the vulnerability and the affected product.