If a long user name is used in a username/password combination in a site URL (such as " http://UserName:Password@example.com"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
Si se emplea un nombre de usuario largo en una combinación nombre de usuario/contraseña en una URL de un sitio (como " http://NombreUsuario:Contraseña@ejemplo.com"), el mensaje modal resultante se mantendrá en un estado sin respuesta o se cerrará inesperadamente, provocando una denegación de servicio (DoS). La vulnerabilidad afecta a Firefox en versiones anteriores a la 55.
USN-3391-1 fixed vulnerabilities in Firefox. The update introduced a performance regression with WebExtensions. This update fixes the problem. Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit these to conduct cross-site scripting attacks, bypass sandbox restrictions, obtain sensitive information, spoof the origin of modal alerts, bypass same origin restrictions, read uninitialized memory, cause a denial of service via program crash or hang, or execute arbitrary code. Various other issues were also addressed.
