Security aspects concerning code written in the programming language PHP which is often used for web applications.

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0
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2answers
114 views

Is my code using mysqli_real_escape_string and quotes100% safe against SQL Injection?

My code is: SELECT * FROM tlb_members WHERE username="{mysqli_real_escape_string($_GET['test'])}" I'm searching and some people said using quotes in SQL statements is safe. Is this true?
3
votes
1answer
62 views

PHP - Is it safe to file_put_content raw HTML?

I'm planning to create a website to let people edit/customize their stories. Let's say the stories will store a lot of html tags ( paragraph, images & video ) I'm thinking using some javascript ...
3
votes
1answer
68 views

How could an attacker read the content of php session variables?

In my PHP code, I am generating an RSA keypair, sending the public key to the visitor and storing the private key in a session variable. Is it possible that an attacker might somehow be able to read ...
0
votes
2answers
58 views

PHP Image Upload - Security of storing outside root and accessing via readfile()

I recently began storing image uploads outside the webroot and retrieving them via readfile(). I implemented this and it's working fine, but I was curious if there are any further vulnerabilities that ...
4
votes
4answers
161 views

Why there are so many web servers which get exploited by generating obfuscated files?

TL & DR How do those obfuscated files many users complain on this SE-site about get on their systems? And after that, even more interesting how they get executed? Is this caused by the way php ...
24
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3answers
3k views

Is it safe to allow www-data to execute privileged commands?

I have noticed several questions on Stack Overflow, like this one, about executing commands with root privileges using PHP. The answer proposed to add the line www-data ALL=(ALL) NOPASSWD: ALL to ...
2
votes
1answer
376 views

Are LFI attacks possible (removing extension) in PHP 5.4.4+?

Wondering if there was a possible attack vector still around for LFI attacks that remove the file extension. Obviously the null byte was fixed in previous PHP versions and no longer works, along with ...
2
votes
0answers
94 views

How could someone trick Norton Safe Web into thinking my website has PHP files that don't exist?

I'm in a bit of a quandary over Norton Safe Web's rating of my company's website. My question is: is it possible for someone to fool Norton Safe Web into thinking that our website has PHP files which ...
5
votes
1answer
271 views

DVWA - Command Injection (high level)

I am attempting to educate myself further on web securities using DVWA. I am stumped on Command Injection, on the high level The help states The developer has either made a slight typo with the ...
3
votes
0answers
73 views

What is the best way to lock down web service access permissions?

After everything what I did in order to protect my server, i have uploaded webshell (WSO 2.1 Web Shell) , to see how far can hacker go and gues what, I was shocked, because I was able to read very ...
69
votes
5answers
15k views

Found suspicious, obfuscated PHP file. Is this a hack attempt on my website? [duplicate]

I just noticed that the top line of my index.php file got changed to what's below. <?php ...
0
votes
1answer
211 views

Please help me understand this PHP hack [duplicate]

We have found this on a hacked PHP webserver. It was in a single file. This file was included from somewhere else with @require. That's what we know: This site is running PHP 5.3 The site had ...
3
votes
1answer
173 views

Is this PHP TOTP (time based one time password) idea sound?

Disclaimer: I am not very familiar with safety techniques in general. The problem: Quickly create lots of small files in server from a bash script. I used to use scp (secure copy) in order to create ...
0
votes
1answer
119 views

Secure Image Upload, or Bypassing PHP mime-type Check

When securing image uploads there are basically three approaches I know of (of course, ideally, all three are used): check file extension store uploaded files in non-executable directory outside the ...
1
vote
1answer
96 views

what is the best way to know if the entered decryption key is correct?

I was searching for a way to store the encryption key of AES_ENCRYPT and found a good answer here: where to store a key for encryption However, now I am trying to use "Type in the encryption key when ...
-2
votes
1answer
109 views

Whats the most secure way to send user data from client to server? [closed]

I know there are probably many existing answers to this question but so far I couldn't find a simple detailed answer. On the android app there is two buttons, sign in with facebook and sign in with ...
0
votes
1answer
114 views

Secure implementation of user login

Well, I created login which works pretty fine, but I'm worried about its security. For checking if user is logged in I use only this $auth = $_COOKIE['authorization']; header ...
4
votes
1answer
2k views

Website Login Security (Secure enough?)

I'm making a bigger site for the first time so security really matters, unlike for my really-bad boards with maybe 10 users. So I wanted to ask if the way I'm doing it is secure enough for a semi-big ...
0
votes
1answer
71 views

Safest way to access data from an SQL server

I am part of a group developing an iOS application. This app accesses a database to both retrieve and submit data. One of the group members said that he does not want to have any direct interaction ...
2
votes
3answers
310 views

How do web email clients store my passwords from other providers?

The situation comes down to this: When I enter in hotmail, it retrieves my messages connecting to other providers: they could only do so by using my email and password. Since I had signed in a ...
0
votes
1answer
44 views

Any vulnerabilities in user input to web Server running Apache and PHP?

There is understandably a lot of emphasis on sanitizing user input handed off to PHP on a web server and numerous opinions on doing it. Can someone please confirm there is no security problems with ...
10
votes
3answers
12k views

How do crackers upload php scripts to Wordpress' wp-content directory?

I've seen a site that has been attacked by uploading php scripts (presumably some sort of shell, or code that loads a shell) to Wordpress' wp-content/uploads directory. Usually this directory is used ...
5
votes
2answers
609 views

Exploiting a PHP server with a .jpg file upload

I would like to ask a question regarding the classic uploading an image and executing php code exploit on a website. So I have been trying out this exploit a website I'm supposed to hack (It's set up ...
8
votes
4answers
1k views

Making a Blacklist of filetypes to protect PHP application

I'm working in a PHP system where the user can upload files. I'm trying to protect the system from malicious codes, so I'm thinking about some type of blacklist of files that I've to block from ...
3
votes
2answers
92 views

Is URL redirection in PHP safe if I use ../../ as a prefix?

I am developing a PHP web app and I'm in the process of implementing a redirection functionality. I know that redirection can be dangerous when it can be set on the client side and I use ../../ as a ...
3
votes
1answer
53 views

Restrict user from executing shell commands using PHP

Let's say that i have shared hosting and i want to secure that place, from executing shell commands. I'v installed suphp, so that users can execute PHP separately. I also did some other things in ...
0
votes
1answer
91 views

How to prevent hotlinking on binary content served through PHP?

I am trying to secure a byte serving script, written in PHP, mostly taken from http://www.tuxxin.com/php-mp4-streaming/ to protect against linking the video directly and easy downloading. I therefore ...
5
votes
1answer
82 views

How can I exploit a PHP endpoint that lets me instantiate an arbitrary class?

PHP lets you instantiate classes from variables or array entries, like this: class Foo {} $className = 'Foo'; new $className(); $someArray = ['class_name' => 'Foo']; new ...
1
vote
1answer
66 views

How to check third party code for Security? [closed]

This may be a very broad question. I am a software developer and from time to time we use third party components which may / may not be secure. Are there any basic things that I should check the ...
0
votes
2answers
330 views

Possible hack on site?

I found a strange file on one of my servers containing the code below. The file was last modified one week ago at 1.40AM in the night, which is a bit odd. I have done lots of changes on this site ...
-5
votes
2answers
115 views

Is this something exploitable in this code?

Is there any possibility to pass this weak comparison? Can user input a file with an extension not contained in $allowed and get past the security check? $allowed = array('txt','docx'); if ...
5
votes
1answer
115 views

sqlmap HTTP 405 error on a vulnerable POST parameter

For academical purposes I need to explode a blind sql injection on a form paramater which is sent using the POST method. The form is very simple, it just has an input text box where to introduce the ...
1
vote
1answer
59 views

Forcing response headers

I'm testing a particular vulnerability box since yesterday and I came with one rather strange problem that I didn't expect. Lets say a vulnerable web-application offer image file upload. The image ...
8
votes
2answers
2k views

Does bcrypt compare the hashes in “length-constant” time?

I saw this function slowEquals() while reading Salted Password Hashing - Doing it Right, which uses a byte-level xor comparison to avoid timing attacks. I was wondering whether this is what Bcrypt ...
1
vote
2answers
108 views

PHP security hacking question, may be more than just PHP

I have an input box for for INSERTing into the database. It is written in PHP PDO. Some one typed in: <"'> and also: ' onClick='alert(1); I'm assuming they were in two different input ...
4
votes
1answer
162 views

Pentesting Web Server for Remote File Inclusion

For educational purposes, I am in the process of pentesting a web server of mine(running on Windows) where there is a Remote File Inclusion vulnerability. I can already get simple things like command ...
6
votes
1answer
67 views

Proper way to protect against XSS, when output is directly into JS not HTML?

I'm seeing plenty of examples when the output is going into HTML directly, but I'm seeing more conflicting information when the output is going straight into JS. For example if the code was: var ...
8
votes
1answer
90 views

HTTP Response Splitting and PHP

There are numerous references to HTTP Response Splitting (HRS) vulnerabilites with PHP having been resolved since 4.4.2 and 5.1.2 (E.g. https://en.wikipedia.org/wiki/HTTP_response_splitting), or for ...
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votes
1answer
64 views

Using and creating a custom 2 way encryption function [closed]

I am trying to create a 2 way encryption function using PHP. As yet I do not have a very good system at all, it is severely flawed and highly insecure, it is using a substitute cipher running from ...
2
votes
1answer
69 views

Are PHP magic methods really necessary for PHP object injection?

I'm trying to understand the PHP Object Injection flaw in vBulletin 5.1.x (CVE 2015-7808) and I stumbled across the requirements for Object Injection as stated by OWASP: The application must have ...
2
votes
1answer
108 views

Offering a privacy scenario with PHP mcrypt library

first of all, sorry if my question is not clear, because English is not my first language. Anyway, let-me explain the concept I'm struggling to solve as the best solution. I have some guys, and they ...
29
votes
4answers
2k views

How to encrypt in PHP, properly?

How do I encrypt data in PHP, properly, using symmetric-key encryption? I have a message M and a secret S. I'm looking for a solution that uses cryptography properly without making any of the usual ...
4
votes
2answers
490 views

PHP code injection using GET and echo

I have found a piece of this code in a web application (simplified): <?php $password="very-secret-password"; $param = $_GET["param"]; ?> <html> ... Param: <?php echo $param; ?> ... ...
43
votes
6answers
10k views

How to Securely Implement a “Remember Me” Feature?

Assuming you already have a website that implements all of the standard login stuff, what is the correct and most secure way to allow users to automatically be logged in for a certain time period ...
9
votes
4answers
10k views

PHP functions for preventing XSS

Is there a proven library with functions for preventing XSS attacks? Many people don't realise that htmlspecialchars is not enough to prevent XSS attacks. There are various contexts that need their ...
3
votes
1answer
327 views

What are the alternatives to null byte injection attack?

Now that Null byte injections no longer work on PHP, what are the alternative attack strategies used by attackers for remote file inclusion ?
-1
votes
1answer
74 views

Token in URL changes on click [closed]

Logging into OpenCart admin, I find a token in its URL: http://localhost/opencart/admin/index.php?route=common/dashboard&token=xOHq2UzQ0YwKTubXgxNpGFySmAA9W90z The synchronizer token pattern is ...
21
votes
4answers
22k views

How to hijack a session?

Despite the blatant title of the question, this is actually for a genuine purpose. My site uses PHP code like this: $select="select id from tableA where user_id='".$_SESSION['sess_user_id']."'"; ...
1
vote
1answer
46 views

Logout CSRF Protection [duplicate]

I am making a CMS and I have a CSRF protection in settings, new article. Should I also put this protection in the logout ?
0
votes
1answer
45 views

Create mod page for an anonymous website

I developed a website. There is no login section in the website. I didn't want to force people to sign up. Now I have a problem. There are a few .php pages that only I should access. How can I do ...