CVE-2025-57974 is a vulnerability classified as CWE-79, which corresponds to Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting (XSS). This specific vulnerability affects the TZ PlusGallery product developed by tuyennv, up to version 1.5.5. The issue is a Stored XSS vulnerability, meaning that malicious input submitted by an attacker is stored by the application and later rendered in web pages without proper sanitization or encoding. This allows an attacker to inject malicious scripts that execute in the context of other users' browsers when they view the affected pages. The CVSS v3.1 base score is 5.9, indicating a medium severity level. The vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L) reveals that the attack can be performed remotely over the network (AV:N) with low attack complexity (AC:L), but requires high privileges (PR:H) and user interaction (UI:R). The scope is changed (S:C), meaning the vulnerability affects resources beyond the initially vulnerable component. The impact on confidentiality, integrity, and availability is low to medium (C:L/I:L/A:L), consistent with typical Stored XSS risks. No known exploits are reported in the wild yet, and no patches or fixes have been linked at the time of publication. Stored XSS vulnerabilities can be leveraged to steal user credentials, perform actions on behalf of users, or deliver malware, especially in web applications that manage sensitive or privileged content. Given the requirement for high privileges, exploitation likely targets authenticated users with elevated rights, such as administrators or content managers, increasing the potential damage within the affected environment.

For European organizations using TZ PlusGallery, this vulnerability poses a risk primarily to the confidentiality and integrity of user sessions and data. Since the vulnerability requires high privileges and user interaction, the threat is more significant in environments where multiple users with elevated access manage or interact with the gallery content. Attackers could exploit this flaw to execute malicious scripts that hijack sessions, deface content, or manipulate gallery data, potentially leading to reputational damage and loss of trust. In sectors such as media, education, or cultural institutions that rely on web galleries for content presentation, the impact could extend to unauthorized data disclosure or disruption of service. Additionally, the changed scope (S:C) indicates that exploitation could affect components beyond the TZ PlusGallery module itself, potentially impacting other integrated systems or user accounts. Although no known exploits are currently active, the presence of this vulnerability in a web-facing application increases the attack surface for European organizations, especially those with complex user roles and permissions. Compliance with GDPR and other data protection regulations may also be at risk if personal data is exposed or manipulated through this vulnerability.

To mitigate this vulnerability effectively, European organizations should: 1) Immediately audit the use of TZ PlusGallery within their environments and identify all instances and versions deployed. 2) Apply any available patches or updates from the vendor as soon as they are released; if no patch is currently available, consider disabling or restricting access to the affected module until remediation is possible. 3) Implement strict input validation and output encoding on all user-supplied data within the gallery application, especially for fields that accept rich content or HTML input. 4) Enforce the principle of least privilege by reviewing and limiting user roles with high privileges to only those necessary, reducing the risk of exploitation by privileged users. 5) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in the web application context. 6) Monitor web logs and user activity for unusual behavior indicative of XSS exploitation attempts. 7) Educate users with elevated privileges about the risks of interacting with untrusted content and the importance of cautious behavior when clicking links or opening content within the gallery. 8) Consider deploying web application firewalls (WAF) with rules tuned to detect and block XSS payloads targeting the TZ PlusGallery application.