CVE-2025-50538 is a cross-site scripting (XSS) vulnerability classified under CWE-79, affecting FlowiseAI's Flowise product versions prior to 3.0.5. The flaw arises from improper neutralization of input during web page generation, specifically allowing injection of IFRAME elements into chat logs. When an administrator views these logs, the malicious IFRAME executes, enabling an attacker to run arbitrary scripts in the admin's browser context. The vulnerability does not require any privileges (PR:N) but does require user interaction (UI:R), meaning the admin must open the affected chat log for exploitation. The scope is changed (S:C), indicating that the vulnerability can affect resources beyond the vulnerable component, such as user session tokens or sensitive data accessible to the admin. The CVSS v3.1 base score is 8.2, reflecting high severity due to the potential for complete confidentiality compromise (C:H), limited integrity impact (I:L), and no availability impact (A:N). No public exploits are currently known, but the vulnerability was reserved in June 2025 and published in October 2025. The lack of a patch link suggests that a fix may be pending or recently released in version 3.0.5 or later. The vulnerability is particularly dangerous because it targets administrators, who typically have elevated privileges and access to sensitive information, increasing the potential damage of a successful attack.

For European organizations, this vulnerability poses a significant risk to the confidentiality of sensitive data managed through Flowise, especially in environments where administrators frequently review chat logs. Successful exploitation could lead to session hijacking, unauthorized access to administrative functions, or leakage of confidential information. Given the administrative context, the integrity of system configurations could also be indirectly affected if attackers leverage stolen credentials or sessions. The vulnerability does not impact system availability directly but could facilitate further attacks that do. Organizations in sectors such as finance, healthcare, and critical infrastructure that rely on Flowise for AI workflow management are particularly vulnerable. The cross-site scripting attack vector also increases the risk of supply chain or insider threats if attackers can inject malicious content into logs viewed by multiple administrators. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as public proof-of-concept exploits may emerge post-disclosure.

To mitigate CVE-2025-50538, European organizations should immediately upgrade Flowise to version 3.0.5 or later, where the vulnerability is addressed. Until patching is complete, restrict administrative access to trusted personnel only and enforce strict access controls on chat logs. Implement web application firewalls (WAFs) with rules to detect and block suspicious IFRAME injections or XSS payloads targeting the admin interface. Sanitize and validate all user-generated content before it is rendered in the chat logs, employing context-aware encoding to neutralize HTML and script elements. Monitor administrative sessions for unusual activity that could indicate exploitation attempts. Additionally, conduct security awareness training for administrators to recognize suspicious content in chat logs. Regularly audit and review logs for signs of injection attempts. Finally, coordinate with FlowiseAI support for any interim patches or workarounds and stay updated on official security advisories.