При отображении страницы в фрейме используется кодовая страница родительской страницы, что позволяет организовать атаку межсайтового скриптинга за счет выбора, например UTF-7, EUC-JP (SHIFT_JIS).
CVE-2007-1115 (The child frames in Opera 9 before 9.20 inherit the default charset from the parent window when a charset is not specified in an HTTP Content-Type header or META tag, which allows remote attackers to conduct cross-site scripting (XSS) attacks, as demonstrated using the UTF-7 character set.)
CVE-2007-1114 (The child frames in Microsoft Internet Explorer 7 inherit the default charset from the parent window when a charset is not specified in an HTTP Content-Type header or META tag, which allows remote attackers to conduct cross-site scripting (XSS) attacks, as demonstrated using the UTF-7 character set.)
CVE-2007-0996 (The child frames in Mozilla Firefox before 1.5.0.10 and 2.x before 2.0.0.2, and SeaMonkey before 1.0.8 inherit the default charset from the parent window, which allows remote attackers to conduct cross-site scripting (XSS) attacks, as demonstrated using the UTF-7 character set.)
