Security aspects concerning code written in the programming language PHP which is often used for web applications.
10
votes
3answers
604 views
What steps should be taken to validate user uploaded images within an application?
Recently I have worked on a number of applications that need to process user uploaded images steps have been taken to validate the extension and the mime type.
But what else can be done to ensure ...
15
votes
4answers
4k views
How did anonymous use UTF-16 ASCII to fool PHP escaping?
A few months ago, anonymous took down a child pornography site using SQL-injection. I read in this article that anonymous claimed that "the server was using hardened PHP with escaping," but they were ...
6
votes
3answers
3k 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 ...
17
votes
3answers
3k views
What are the best practices for hardening a php.ini file?
In order to secure a PHP installation, what are the best settings for a php.ini file? What is absolutely vital in terms of security? What is recommended for most use cases?
22
votes
5answers
2k views
How to perform a security audit for a PHP application?
I have a PHP application that I would like to have audited for security. I'm familiar with most of the general security issues, but want to make sure I didn't miss anything.
What steps should I take ...
25
votes
5answers
2k 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 ...
11
votes
2answers
2k views
Multibyte character exploits - PHP/MySQL
Could someone please point me to a link with some information on multibyte character exploits for MySQL? A friend brought them to my attention, but I've not been able to find much information on the ...
7
votes
3answers
513 views
Security attacks on PHP web applications
I know about following security attacks on php applications (html,php,js).
XSS
SQL Injection
CSFR
Session Hijacking /Fixation
Code Injection
Remote file injection
Should i know about any other or ...
11
votes
4answers
454 views
what to do after suspected intrusion on hobby webserver
I maintain a server to host my files and a number of websites for hobbies and friends. I just noticed that the site summary being returned in google for one of my domains were all porn related ...
12
votes
3answers
498 views
How secure is aSSL (javascript)? Does it effectively mimic SSL?
Some of you may be familiar with the aSSL project, which uses AJAX/PHP to mimic the SSL protocol. It uses RSA 512 or 1024 for the keys, and AES for the actual data. It looks impressive to me in ...
6
votes
5answers
1k views
Why do people say that PHP is inherently insecure?
I've heard it said that PHP is inherently insecure. Is this true? Why?
4
votes
5answers
4k views
Mysql - two-way encryption of sensitive data (email addresses) outside of Apache, PHP and MySQL
We store user email addresses in our database, like many other websites. While we do take pride in the security measures in place, sometimes "just enough" is just not enough.
We've begun looking into ...
30
votes
3answers
1k views
Security Review - password_hash implementation for PHP
I'm currently working on a "helper function" for PHP's core to make password hashing more secure and easier for the majority of developers. Basically, the goal is to make it so easy, that it's harder ...
12
votes
2answers
1k views
How to do Ajax securely?
This question is inspired by this security question http://security.stackexchange.com/questions/1707
What are the threats in using Ajax? (Please note I am talking about security threats, not ...
18
votes
4answers
4k views
How do you know your server has been compromised?
I recently helped a client who had their server hacked. The hackers added some PHP code into the header of the homepage redirecting the user to a porn website — but only if they came from Google. This ...
3
votes
7answers
2k views
Server compromised for 2nd time, cannot locate source of attack
I need some help tracing a vulnerability on my server. For the second time, my server has been compromised with files being replaced with virus-ridden downloads.
According to the filesystem dates, ...
10
votes
2answers
2k views
Is strip_tags() horribly unsafe?
I always use strip_tags to prevent XSS attacks, but today I saw a post which was telling it's horribly unsafe. As the manual says, it doesn't check for malformed HTML!
Is it true?
What can I do to ...
7
votes
3answers
392 views
Finding security consultant for doing in-depth code review?
We have a PHP application that we know has poor coding practices (because the developers did not have a good understanding of PHP / programming fundamentals). This could lead to the scenario where we ...
6
votes
3answers
894 views
PHP mail() Header Injection Prevention
This site nicely explains the problem. Essentially, nearly all php mail() examples that are given are vulnerable to header injection attacks. The referenced site gives a regex sanitation solution ...
3
votes
3answers
1k views
How insecure are PHP's rand functions?
There are some pseudo-random-number generators in PHP: rand(), srand(), mt_rand(), mt_srand(). You can look at their code here.
I understand those functions are insecure, but how insecure are they?
...
10
votes
6answers
1k views
Security review: “HTTP header user-agent has been set to (something)”
We got a security review done of our PHP code and they team advised this in their report (amongst other things):
/appdir/
Details
The HTTP header user-agent has been set to \" .
Request
GET ...
4
votes
2answers
587 views
How to find and protect against the exploited vulnerability in a PHP application based on the logged URL?
I have been attacked on a shared host server and they said I should configure my own php.ini file properly.
I have a little PHP/MySQL program with a registering function, a little admin site.
...
13
votes
1answer
580 views
Risks of a php image upload form
So I have a client wants a photography site where users can upload their photos in response to photography competitions. Though technically this isn't a problem, I want to know the risks associated ...
21
votes
5answers
771 views
Should passwords be revealed in error message?
I am having pet-peeve with PHP's PDO class. As you can see on the Warning note: it reveals database password by default if an exception was not caught (when display errors is on which is a probable ...
15
votes
4answers
3k 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']."'";
...
4
votes
4answers
733 views
What security features should a PHP framework have?
What security features would you find useful or expect from a PHP framework? I have a PHP framework that I've developed that I'm going to be releasing as an open source project, but I want to make ...
18
votes
3answers
3k views
How does “check.torproject.org.” know if you're using TOR?
I'm looking at the results from the following URL and would like to know how does the TOR website "know" that TOR is being used or not.
...
12
votes
3answers
516 views
Getting a manual security code review done - What to watch out for?
We have a PHP application that we want to get code reviewed from an external security consultant, but I'm not clear on "how to" go about that process.
We did specify what kind of tests he should be ...
8
votes
5answers
606 views
Scripting a search through php files for dangerous calls for manual review
I'm automating a script which searches through all php files on a big site for dangerous commands. The files which are found will be manually code reviewed.
Does anyone have any recommendations for ...
6
votes
2answers
755 views
when to use nonce?
I have trouble understanding nonce. I read a very good answer related to nonce by @Thomas Pornin, but it is too complicated for me as I am new to cryptography. From what I know, nonce is used to ...
4
votes
1answer
484 views
Is this admin area secure enough? V2
This is a response to my previous question, Is this admin area secure enough?.
There were some very helpful answers there, for which I am very grateful. So I went back to the drawing board and here ...
4
votes
2answers
396 views
Is it a secure way to declare DB parameters in htaccess rather than in a PHP file?
It has been suggested in securing PHP article that using directive as below in htaccess is more secure than hardcoding it into your app:
<VirtualHost ilia.ws>
Include /home/ilia/sql.cnf
...
37
votes
5answers
2k views
Password security in databases - today still best practice? [duplicate]
Possible Duplicate:
Which password hashing method should I use?
There are a ton of great posts about password security in databases on stack overflow and on other sites and as I am ...
9
votes
2answers
2k views
How to address XSS security issues in FCKeditor / CKeditor?
A security report we conducted through an outside company reported XSS vulnerabilities in FCKeditor which we're using in our PHP application.
They pointed out that accessing URLs such as:
...
7
votes
2answers
177 views
Sending data form registration forms
I understand that sending data from the user to the server, unencrypted, is a bad practice. That is logical.
So how do I encrypt 'userside' and send the data to the server in encrypted form?
Can ...
6
votes
2answers
488 views
DB Passwords: More Secure in a PHP App's .ini config files or apache2 environment variables?
I manage a php app whose key variables (such as database server addresses, DB user names and passwords, etc) change depending on their environment (Dev, QA, Production, etc.).
In order to simplify ...
6
votes
1answer
675 views
Do I have to make any more check if I use prepared statements for integers?
I am currently using PDO with prepared statements for some integer values (see PDO::PARAM_INT). That means I call PDO like this:
$stmt = $conn->prepare("SELECT `lastMove` FROM ".GAMES_TABLE.
...
6
votes
2answers
2k views
php.ini security setting after attack
My website have been attacked and I need a best practice for a php.ini I have done some reading but I am still not sure if I covered most of the options.
here is my settings:
file_uploads = Off
...
5
votes
6answers
730 views
How to defend vs. Image Remote File Inclusion, e.g. RFI using a .gif file (Apache/PHP)?
To defend versus Remote File Inclusion where attackers try to abuse image files, I usually recommend to never use include to include image files into PHP code.
Sometimes though, the avoidance of ...
4
votes
3answers
340 views
Is it secure to centralize database information?
I would know if it is secure to centralize database information into one file like this :
db_infos.php:
$server = "localhost";
$user = "root";
$password = "1234";
$database = "foo";
$table = "bar";
...
4
votes
1answer
448 views
How to prevent CSRF if you want to include Flash plugins in your form like Uploadify in your form?
What is CSRF?
I need a basic definition that is not just lifted from Wikipedia.
I understand SQL injection, XSS, cookie poisoning, but I just cannot wrap my mind around this.
I am using a ...
3
votes
3answers
547 views
optimal way to salt password?
A good way to salt password?
I have read a few answers related to salting password. But I started to get confused.
I came across few functions people used to generate salt like:
mcrypt_create_iv()
...
3
votes
3answers
323 views
Is this admin area secure enough?
EDIT: Please view the revised question instead
The admin area has special access to the database (modifying orders, etc).
To help explain, I drew a diagram, so here is my process:
Notes:
I ...
3
votes
3answers
806 views
Altering a $_SESSION variable in PHP via XSS?
Not sure if what I'm saying makes sense... but is it possible for me to alter a $_SESSION variable from outside the target PHP script?
One of our scripts uses a $_SESSION variable and I'm not sure if ...
1
vote
1answer
290 views
Is this enough to tackle script / malicious code insertion in GET, POST requests?
I've got legacy PHP code which attempts to prevent script / SQL injection with the following:
if (!empty($_POST)) {
reset($_POST);
while (list($k,$v)=each($_POST)) {
...
-2
votes
6answers
948 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 ...
8
votes
4answers
444 views
What information should a error log record?
I want to populate my error log with useful information if and when errors occur. I'd like to use the log to be able to spot and fix bugs on my site, but also to potentially log hack attempts. For a ...
3
votes
3answers
1k views
Do you need to encrypt session data?
I came across a session management class in PHP which encrypts session data in the session storage folder (i.e., /tmp) and can be decrypted later in your script using a key. I was wondering if it's ...
2
votes
3answers
166 views
is it safe to allow external images to be attached to Blog or any Web content?
I am filtering all images that attached to any content of my blog:
Check for file extension.
Check content type using $finfo = finfo_open(FILEINFO_MIME_TYPE);
I also save the image temporary on my ...
2
votes
1answer
106 views
What is a good method to report security breaches that are being used to actively spam?
I received an email the other day purporting to be from a bank I hadn't even heard of, so I decided to poke around. On some quick investigation, it looks like something has just latched onto some poor ...
