CVE-2026-96631

### Summary AdminNeo versions 4.6.0 through at least 5.5.0 are vulnerable to cookie attribute injection via the `X-Forwarded-Prefix` HTTP header. An attacker who can influence this header (e.g., through a reverse proxy that forwards it from clients, an attacker-controlled upstream proxy, or a man-in-the-middle position) can inject arbitrary cookie attributes including `Domain`, `Path`, `Secure`, and `SameSite` into all `Set-Cookie` response headers emitted by AdminNeo. This allows an attacker to expand the cookie scope to an attacker-controlled domain (e.g., `Domain=.evil.com`), causing the victim's browser to send AdminNeo's `neo_sid` (session ID) and `neo_key` (database password encryption key) cookies to the attacker's server on subsequent requests. Originally reported by @retkoussa in Adminer: https://github.com/vrana/adminer/security/advisories/GHSA-c533-9qwm-8w5h ### Vulnerable Code **Root cause 1 - Unsanitized header prepended to `REQUEST_URI`** (`admin/include/bootstrap.inc.php`, lines 50–52): ```php if ($_SERVER["HTTP_X_FORWARDED_PREFIX"]) { $_SERVER["REQUEST_URI"] = $_SERVER["HTTP_X_FORWARDED_PREFIX"] . $_SERVER["REQUEST_URI"]; } ``` The client-supplied `X-Forwarded-Prefix` header is concatenated into `REQUEST_URI` with no validation or sanitization of special characters (specifically semicolons, which delimit cookie attributes). **Root cause 2 - Manual `Set-Cookie `header construction without escaping** (`admin/include/functions.inc.php`, lines 416–424): ```php function cookie(string $name, string $value, int $lifetime = 2592000): void { header("Set-Cookie: $name=" . rawurlencode($value) . ($lifetime ? "; expires=" . gmdate("D, d M Y H:i:s", time() + $lifetime) . " GMT" : "") . "; path=" . preg_replace('~\?.*~', '', $_SERVER["REQUEST_URI"]) . (HTTPS ? "; secure" : "") . "; HttpOnly; SameSite=lax", false); } ``` The tainted `REQUEST_URI` is interpolated directly into the `path=` attribute of the `Set-Cookie` header. Since semicolons a