Cross-Site Scripting (XSS) in V2Board thru 1.7.4. The custom_html field in theme configuration is rendered using Blade unescaped output in public/theme/v2board/dashboard.blade.php. An admin can inject arbitrary JavaScript via the saveThemeConfig API. All site visitors execute the payload, enabling cookie theft, session hijacking, or phishing.

Sensitive server_token exposed via GET parameter in V2Board thru 1.7.4. In app/Http/Controllers/Server/UniProxyController.php, the server authentication token is accepted via GET parameter transmission. The token appears in URLs such as /api/v1/server/UniProxy/user?token=SECRET, causing it to be recorded in web server access logs, browser history, HTTP Referer headers, and proxy/CDN logs. An attacker who gains access to any log source can extract the token and impersonate a proxy server node, potentially intercepting all user traffic.

SQL Injection via ORDER BY clause in V2Board thru 1.7.4. In app/Http/Controllers/Admin/UserController.php, the sort parameter from user input is passed directly to User::orderBy($sort, $sortType) without validation. An authenticated admin can sort users by any database column including password, remember_token, and other sensitive fields, enabling information disclosure through ordering analysis.

V2Board 1.6.1 through 1.7.4 and Xboard through 0.1.9 expose authentication tokens in HTTP response bodies of the loginWithMailLink endpoint when the login_with_mail_link_enable feature is active. Unauthenticated attackers can POST to the loginWithMailLink endpoint with a known email address to receive the full authentication URL in the response, then exchange the token at the token2Login endpoint to obtain a valid bearer token with complete account access including admin privileges.