Linked Questions
12 questions linked to/from Using file extension and MIME type (as output by file -i -b) combination to determine unsafe files?
3
votes
6
answers
28k
views
Use PHP to check uploaded image file for malware?
I want my users to be able to upload a photo. Currently I am not checking the uploaded photo for problems of any kind, although I do limit the size to 32k.
Is there any way for me to check uploaded ...
- 113
8
votes
5
answers
2k
views
How should I serve untrusted / unsanitized documents (PDF, DOC, XLS) to end users over the web?
My website will be hosting documents for end users and I would like to make this as secure as possible.
Question
Assuming that I have a need to share documents on a website that may contain hostile ...
- 50.7k
22
votes
4
answers
14k
views
Is it safe to serve any user uploaded file under only white-listed MIME content types?
Let's say I develop an application that,
Allows any user to upload a file of only white listed mime content type and extensions (word and pdf).
Serves those files with the allowed extension and ...
- 535
20
votes
4
answers
3k
views
Is it safe to store and replay user-provided mime types?
If a user uploads a file but modifies the request by setting the mime-type to something arbitrary, like "superdangerous/blackhatstuff", is it safe for me to send the same mime type back to a different ...
- 1,942
2
votes
4
answers
3k
views
Security risks of hosting user-supplied images?
I have a program that will accept and fetch images from urls. It will check if the extension is .png, .jpg, etc...
I will fetch these files and store them, they will be shown to users in a gallery (...
- 54.4k
29
votes
3
answers
17k
views
How can I be protected from pictures vulnerabilities?
I've just read this question What is the corrupted image vulnerability? How does it work?
(GIFAR, EXIF data with javascript, etc..)
I'm asking myself how can I protect myself and my website's users.
...
- 393
20
votes
3
answers
23k
views
Does X-Content-Type-Options really prevent content sniffing attacks?
In Tangled Web Michal Zalewski says:
Refrain from using Content-Type: application/octet-stream and use application/binary instead, especially for unknown document types. Refrain from returning ...
- 5,357
14
votes
3
answers
26k
views
Is it possible to inject HTML into image to provoke XSS?
Some answers mention that it's possible to inject attacker-controlled HTML into images and therefore provoke XSS.
I guess that this HTML will be processed by browser only if hole exists in browser. ...
- 5,357
8
votes
3
answers
3k
views
How to safely allow upload of executable files [duplicate]
I need help regarding file uploading. In one of my projects the client wants to allow a file upload without restrictions on the file type. But I'm afraid that then users can upload executable files ...
- 89
1
vote
2
answers
448
views
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 ...
- 65
16
votes
1
answer
17k
views
Preventing Server-Side Request Forgeries in Java
The application lets users specify a URL for their profile picture. It fetches the data from the URL and saves it on the server. However, the app is vulnerable to server-side request forgery (SSRF) - ...
- 33.4k
2
votes
1
answer
639
views
How confident is MIME blacklisting on a proxy server?
We are blacklisting a number of MIME types on our proxy server so users can't download certain file types, for example, executables.
Could it be possible that somehow, a malicious server can trick a ...
- 23