CVE-2025-58026 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the Termageddon: Cookie Consent & Privacy Compliance product up to version 1.8.1. This vulnerability arises due to improper neutralization of input during web page generation, allowing malicious scripts to be stored and later executed in the context of users visiting the affected web pages. Specifically, an attacker with at least low privileges (PR:L) and requiring user interaction (UI:R) can inject malicious payloads that are stored persistently within the application. When other users access the compromised pages, the injected scripts execute, potentially leading to the compromise of user sessions, theft of sensitive information such as cookies or tokens, and unauthorized actions performed on behalf of the victim. The vulnerability has a CVSS v3.1 base score of 6.5, indicating a medium severity level. The attack vector is network-based (AV:N), with low attack complexity (AC:L), but requires some privileges and user interaction. The scope is changed (S:C), meaning the vulnerability affects components beyond the initially vulnerable component, impacting confidentiality, integrity, and availability to a limited extent (C:L/I:L/A:L). No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that mitigation may rely on vendor updates or configuration changes once available. The vulnerability is significant because Termageddon is a widely used service for managing cookie consent and privacy compliance, which is critical for GDPR adherence and user trust on websites. Exploitation could undermine the security posture of websites relying on this product, leading to reputational damage and regulatory consequences.

For European organizations, the impact of this vulnerability is particularly critical given the stringent data protection regulations such as GDPR that mandate robust privacy compliance mechanisms. Since Termageddon is used to manage cookie consent banners and privacy compliance notices, exploitation of this Stored XSS vulnerability could allow attackers to hijack user sessions, steal personal data, or manipulate consent settings, thereby violating user privacy and regulatory requirements. This could lead to significant legal penalties, loss of customer trust, and damage to brand reputation. Additionally, the ability to execute scripts in the context of the affected websites could facilitate further attacks such as phishing, malware distribution, or lateral movement within the victim’s infrastructure. Organizations that rely heavily on Termageddon for compliance, especially those handling sensitive or personal data of EU citizens, face increased risk of data breaches and non-compliance fines. The medium severity score reflects the need for timely remediation to prevent exploitation, particularly in sectors like finance, healthcare, e-commerce, and public services where privacy compliance is paramount.

To mitigate this vulnerability effectively, European organizations should: 1) Monitor Termageddon’s official channels for security patches or updates addressing CVE-2025-58026 and apply them promptly once available. 2) Implement strict input validation and output encoding on all user-supplied data related to cookie consent and privacy compliance interfaces to prevent injection of malicious scripts. 3) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 4) Conduct thorough security testing, including automated scanning and manual penetration testing focused on XSS vectors within the Termageddon integration points. 5) Limit privileges of users who can modify cookie consent configurations to reduce the risk of malicious input injection. 6) Educate web administrators and developers about secure coding practices related to web page generation and user input handling. 7) Consider implementing web application firewalls (WAFs) with rules specifically targeting XSS attack patterns to provide an additional layer of defense. 8) Review and audit existing consent management implementations to identify and remediate any unsafe handling of user inputs. These measures, combined with vendor patches, will help reduce the risk of exploitation and protect user data and organizational compliance.