MISP contains a reflected cross-site scripting (XSS) vulnerability in the analyst data notes panel. The seed path parameter, supplied by the user via the URL, was passed directly into inline JavaScript within the rendered HTML response without any sanitization or type enforcement. An attacker who can convince an authenticated MISP user to navigate to a crafted URL (for example, via a phishing link) can inject arbitrary JavaScript that executes in the victim's browser context. This may allow the attacker to read session tokens, manipulate the page, or perform actions on behalf of the victim. Preconditions: - The victim must be authenticated to MISP and access the analyst data view for an attribute or object. - The attacker must supply a malicious seed value in the URL path. Impact: - Execution of arbitrary JavaScript in the victim's browser session. - Potential theft of session credentials or sensitive data visible in the page. - Manipulation of the analyst data interface. Affected: MISP versions prior to the fix (commit 58925dbf0, post v2.5.48).