PHP - Is It A Security Risk?
If I check and make sure a variable is numeric with the is_numeric function, and it passes the in_numeric function, can it still be a security risk if I don't escape it with mysql_real_escape_string()?
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I am trying to install a script on my OpenSuse Webserver, and I managed to resolve most of the errors except of one: The value for session.save_path (/tmp) is not writable for the web server. Make sure that PHP can actually save session variables.
That seems to be the problem.
session.save_path: writeable You need set permission for your var directory.
well - i guess that the default ownership may be incorrect on the session folder: Example; php on some Linux-Server defaults to apache user. If using nginx or other need to switch the folder ownership. Also as a note you have to change the user/group setting in www.conf.
chown -R root:nginx /var/lib/php/7.0/ sed -i 's/apache/nginx/g' /etc/php-fpm-7.0.d/www.conf service php-fpm-7.0 restart
But wait: what about the security - is it save to make the session.save_path writeable!? my server-admin says that this is a big big hole and makes the server unsecure. love to hear from you yours dil_bert by the way: years ago i have had this issue on the server. but the question is - is this a securitiy risk!? I need to know this. Look forward to hear from you Edited March 21, 2020 by dil_bert I read ages ago (and checked to see if it's true, it was and given how it works, it must still be) the end user can alter the value of any form field, using Firebug or similar, before submitting it. Two things I've figured out today: 1) a form input doesn't need a value - doesn't even need the attribute - if you're only checking whether the POST var isset and the actual value isn't important 2) Although it appears not to matter in the example I'm working on now, if the script doesn't check what the value is, and potentially sanitise it, the user could submit the form with any value, true, false, malicious, idk... So my question is: is this one of the ways malicious bad things can happen and do I *have to* specify a value, not because the script won't work without it, it does, but because in the real world it opens a security door if I don't check for malicious script by saying "if value not as expected, script has to die". Having formulated the question properly and thought about it I can't imagine simply making a form, without obvious connections to anything important, could be a problem in the way I'm asking about but I asked it now so Edited by appobs, 03 July 2014 - 12:08 PM. This is a two parter... mostly a discussion as I am currently not employing the purpose of these "things"
I am creating an autoparsing webapp that has unlimited use... whatever a person can think of
It accesses camera, microphone, gyro/accelerometer, flash etc... mostly it takes in data and does something to it according to the parsing tool
I'm not saying this is new, in fact I spent a while using Touch Develop which is a scripting "thing" by Microsoft, the problem was lag
That is another thing that concerns me, without web access the web-app is useless right? So I'm wondering if it is possible to copy your current setup and either translate it to the mobile languages like Java, C#/XML, Objective C or somehow a platform independent alternative
Anyway...
I'm not sure if I can access front end code, like <div class="whatever"> safely using injection
Well injection you just bind parameters but what if the incoming string is literally malicious ?
Also as far as autoparsing optimization goes, what I mean by that is
I intended to create a character by character comparison, obviously or at least to me, starting with easier stuff first like
for example a link is entered
http://www.something.com
then the autoparser compares each character one at a time from left to right
|1|2|3|4|5|6|7|8|9|10|
|h|t|t|p|:|/|/|w|w|w|...etc...
But I would check for existing formats starting with the shortest first and also checking from right and left, eg. .mp4 is obvious as a file type
I'll have more once I actually know what I need just looking to discuss I suppose... sorry if that is not appropriate feel free to delete this thread
In the future the users who have modified their personal accounts would benefit from an "AI" thing that is specific to their personalities based on what they have enabled
Edited by greenace92, 28 December 2014 - 09:37 AM. Besides "mysql_real_escape_string"ing all the user input what other security strings should you definitely include n your site? hi php freaks I am using pdo as the driver for my new app the issue is I can't seem to find a clear answer. I want to sanise the vars that are coming into the database but pdo is suppose to fix all the issues. Is this true what other things do I need to watch for when using pdo they must have some flaws. Thanks Hi there, I'm in serious need to find a way to block people from a website I code for. The thing is, we have a jailing system, nice and simple, and IP/email ban system too. But with proxies, advertisers and repeated troublemakers keep coming back because we just get the new proxy IP each time and it's a losing battle. What I need is a way to ban them properly from the site, like somehow stopping the computer they use from accesing the site. someone once said you can use a cookie to stop a browser getting on the site, but I don't know how to set it up to give the cookies out upon login and find the one associated to an account we don't want (by "cookie" banning I guess?") and stop them from logging in. I really have less idea about website security. Yesterday for the first time I learned website hacking and applied that method to my web page. My webpage was completely down after applying that. Q) To free a site from hacking what techniques are followed? Hi, I am currently working on an Invoice System using PHP and MySQL. However I was just wondering if the system I am using is secure enough. The Client gets a link like this: Code: [Select] mysite.com/?customerid=b3e470c55aad30eb38ee52eec1d8cb52 Each client has a unique "id" I also have an ID for the administrative back-end. I do clean the GET variable before querying the database though. Do I need to secure this with anything else or is this enough, as this is my first time creating anything with PHP and MySQL together. Thanks, mme I have just made a couple of forms that submit data to a mysql database. I was wondering what measures I need to make to in order to keep the whole thing very secure. At the moment I have stripped the inputs of tags and forward slashes. Is there anything else I should do? Also some field in the form allow the user to enter a url. With these fields I have not stripped them of forward slashes. Is this a bad idea? Should I do something like replace the forward slashes with something else and then reverse this process every time I extract that data from the database? I have been working on a website for some time now. My work is now 95% finished and now I am starting to look at security, as I am using PHP. My webpage uses HTML FORMS. When most of these forms get send back to the server, 50% of the time PHP is inserting the value of the FORM inputs into MySQL. To give a basic run down, I have a newsletter sign up system. "Enter your e-mail address"... and then the user enters their e-mail and submits.. PHP runs a MySQL query to insert that FORM value into the database along the lines of this: Quote insert into newsletters (email) values ('.$POST['email'].') I fear this is very vulnerable to injection attack as it means a trouble maker can come along and enter anything they want into my database, potentially wiping it out. I believe I need to "sanitize" my input with a MySQL "real_escape_string" or something? Is there anything real obvious I should look out for when it comes to PHP security? Is there a way to forbid all strings/arguments except the few I need or something perhaps? I want to create an ADMIN directory with several directory under that. I want to be certain that the user cannot log into any of the directory unless they have confirmed login. Is $_session id's the best way to go? Should I create on the flyer and attached to username? What is the best practice for this? Regards, DED Hi everyone I'm kinda new to PHP and have a couple of questions; 1: How secure is PHP, is it very hackable? Are there things you recommend to make it more secure? 2: I am building a little employee system for staff at a friends company and they can view personal information when they login, as well as ordering stuff with online payment through WorldPay. What is therefore the best and most secure way of handling passwords, logins, data, insert statements etc. I basically want to make it as secure as possible and hopefully learn some new skills Any tips or help would be great Thanks Hey, so basically this is what im trying to do: I'm writing an mp3 store, and want the user to be able to play the whole track before purchase. Currently all the music files are in a protected folder with permissions set so access isnt possible. The mp3 player calls play.php?fid=encryptedfileid rather than the direct music link. This is all working perfectly. The bit i am now stuck on is stopping the users going to play.php?fid=encryptedfileid directly and downloading the mp3 directly. How do I make it so the server can execute the play.php file, but the user cannot? I attempted to set a cookie in play.php and deny access if cookie was present, however the server also set the cookie, so this didnt work. See play.php code (in this example, fid is just the filename, but it will be more encrypted, calling to a special md5 hash, albumid and artistid). <?PHP // Define the path to file $filename=$_GET[fid]; $file = "music/$filename.mp3"; if(!$file) { // File doesn't exist, output error die('file not occupied'); } elseif(!file_exists($file)) { die('Error: File not found.'); } else { // Set headers header("Cache-Control: public"); header("Content-Description: File Transfer"); header("Content-Disposition: attachment; filename=$file"); header("Content-Type: application/octet-stream"); header("Content-Transfer-Encoding: binary"); // Read the file from disk readfile($file); } ?> So to clarify, I need the server to access and execute this script with the mp3 player (simple javascript player) and the server not be able to visit play.php?fid=xxx directly to download. Thanks I have nearly finished a website that i am making for my local community, they will be registering on the site and i am wandering what sort of security for the site i should be thinking about. I just dont want someone out there doing something to cause problem with the site and ruining it for everyone else. I'm building an e-commerce website using php and mysql and I'm a bit worried about security issues. The website is going to be handling personal information so I want to make sure that it's secure and that no-one can get hold of it. I don't really have any idea about and security issues or problems that I could run into and perhaps you could point me in the direction or some tutorials that would be really great. Also if anyone here has been in the same situation what did you do to make your site as secure as possible? Thanks for any help. Hi everyone, So, like my name says, I'm just a hobbyist PHPer, but I write the occassional PHP application for people, I've been doing it for quite a while and I fear that perhaps my way of securing my applications may be a bit antiquated... I was hoping that you guys/gals might be able to take a look and give me some help with perhaps how I could go about making these apps more secure... So, without further ado, here it is... standard application page, e.g. index.php Code: [Select] <? session_start(); if(!$_SESSION['Condition'] == 'Logged') { header("Location: login.php"); } elseif($_SESSION['Condition'] == 'Logged') { require "connection.inc"; ?> <? } ?> login.php page Code: [Select] <? if(isset($_POST['Login'])) { include_once 'connection.inc'; $count = 0; $query = "SELECT UserID FROM Users WHERE UserName = '$_POST[username]' AND UserPassword = '$_POST[password]'"; $results = mysql_query($query)or die(mysql_error()); $count = mysql_num_rows($results); while($row = mysql_fetch_array($results)) { $UserID = $row['UserID']; } if ($count == 1) { header("Location: loginaction.php?UserID=$UserID"); } } ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title></title> <link rel="stylesheet" type="text/css" href="StyleSheet.css" /> <script language="javascript" type="text/javascript"> function loginValidate(form) { if (form.username.value == '') { alert('You must supply a Username.'); form.username.focus(); return false; } if (form.password.value == '') { alert('You must supply a Password.'); form.password.focus(); return false; } else { return true; } } </script> </head> <body> <? include_once 'header.inc'; ?> <div id="LoginBox"> <div id="SubFormBoxHeading"> Log In </div> <form id="thisform" action="<? echo $_SERVER['PHP_SELF']; ?>" onsubmit="return loginValidate(this)" method="post"> <table> <tr> <td colspan="2"> <? if (isset($_POST['Login']) && !$count == 1) { echo '<h3>Wrong Username and/or Password</h3>'; } ?> </td> </tr> <tr> <td class="Labels">Username:</td> <td><input type="input" id="username" name="username" size="20" /></td> </tr> <tr> <td class="Labels">Password:</td> <td><input type="password" id="password" name="password" size="20" /></td> </tr> <tr> <td colspan="2"> <div style="text-align: center; margin-top: 20px; margin-bottom: 20px;"> <input type="submit" id="Login" name="Login" value="Log In" /> </div> </td> </tr> </table> </form> </div> <? include_once 'footer.inc'; ?> </body> </html> loginaction.php page Code: [Select] <? session_start(); $_SESSION['Condition'] = 'Logged'; $_SESSION['UserID'] = $_GET['UserID']; header("Location: index.php"); ?> and finally, the logout.php page Code: [Select] <? session_start(); unset($_SESSION['Condition']); unset($_SESSION['UserID']); session_destroy(); header("Location: index.php"); ?> Hi, I am looking to create a directory that can not be accessed using .htaccess and neither can files directly. But I want to make it so when you are signed into joomla you can access the files via a mp3 player on the sight. My mp3 extention is joomline player flplayer. And I heard that if I cange the name of the file in joomla fomr lovelove.com/audio/love/abc.mp3 to lovelove.com/audio/love/abc.php?name=abc and then that abc.php script (inside the script it checks if you are logged in) will retrieve the file name, and the joomline will play it it will work. is this possible? Also, if not what can I do for this to work? Right now my script is not working as the joomline looks up all the mp3 files as one big string. this is the abc.php which on my site its calld psp.php <?php define( '_JEXEC', 1 ); define( 'JPATH_BASE', realpath(dirname(__FILE__).'/../../' )); require_once ( JPATH_BASE .'/includes/defines.php' ); require_once ( JPATH_BASE .'/includes/framework.php' ); $mainframe =& JFactory::getApplication('site'); if( !empty( $_GET['name'] ) ) { // check if user is logged if(JFactory::getUser()->guest) { die( "ERROR: invalid song or you don't have permissions to download it." ); } else { $psp = preg_replace( '#[^-\w]#', '', $_GET['name'] ); $psp_file = "{$_SERVER['DOCUMENT_ROOT']}/audio/live/{$psp}.mp3"; if( file_exists( $psp_file ) ) { header( 'Cache-Control: public' ); header( 'Content-Description: File Transfer' ); header( "Content-Disposition: attachment; filename={$psp_file}" ); header( 'Content-Type: application/mp3' ); header( 'Content-Transfer-Encoding: binary' ); readfile( $psp_file ); exit; } } } ?>then I have joomline player jlplayer <?php /** * JoomLine mp3 player - Joomla mp3 player * * @version 1.5 * @package JoomLine mp3 player * @author Anton Voynov (anton@joomline.ru), Sergii Gaievskiy (shturman.kh@gmail.com) * @copyright (C) 2010 by Anton Voynov(http://www.joomline.ru) * @license GNU/GPL: http://www.gnu.org/copyleft/gpl.html * * If you fork this to create your own project, * please make a reference to JoomLine someplace in your code * and provide a link to http://www.joomline.ru **/ defined('_JEXEC') or die('Restricted access'); function ascii2hex($ascii, $reverse = false) { $hex = array(); for ($i = 0; $i < strlen($ascii); $i++) { $byte = strtoupper(dechex(ord($ascii{$i}))); $byte = str_repeat('0', 2 - strlen($byte)).$byte; $hex[] = $byte; } if ($reverse) $hex = array_reverse($hex); return implode(" ",$hex); } function read_frame (&$f, &$tagdata, $frame) { $pos = strpos($tagdata,$frame); if ( $pos !== FALSE) { // frame found. read length of this frame fseek($f, 10+$pos+4); $frame2len = hexdec(ascii2hex(fread($f,4))); if (($frame2len-1) > 0) { // read frame data fseek($f, 10+$pos+4+2+4+1); $data = trim(fread($f,$frame2len-1)); $hexfdata = ascii2hex($data); if ( substr($hexfdata,0,5) == 'FF FE' or substr($hexfdata,0,5) == 'FE FF' ) { $data = iconv("UCS-2","UTF-8",$data); } else { if (!preg_match('//u', $data)) { $data = iconv("cp1251", "UTF-8",$data); } } return $data; } else { return false; } } else { return false; } } function readmp3tag($file) { $f = fopen($file, 'rb'); rewind($f); fseek($f, -128, SEEK_END); $tmp = fread($f,128); if ($tmp[125] == Chr(0) and $tmp[126] != Chr(0)) { // ID3 v1.1 $format = 'a3TAG/a30NAME/a30ARTISTS/a30ALBUM/a4YEAR/a28COMMENT/x1/C1TRACK/C1GENRENO'; } else { // ID3 v1 $format = 'a3TAG/a30NAME/a30ARTISTS/a30ALBUM/a4YEAR/a30COMMENT/C1GENRENO'; } $id3v1tag = unpack($format, $tmp); // read tag length fseek($f, 8); $tmp = fread($f,2); $tmp = ascii2hex($tmp); $taglen= hexdec($tmp); $tagdata = ""; if ($taglen > 0) { //read tag data fseek($f, 10); $tagdata = fread($f,$taglen); } // find song title frame $title = read_frame ($f, $tagdata, "TIT2"); if (!$title) { if ($id3v1tag['TAG']== 'TAG' && ascii2hex(substr($id3v1tag['NAME'],0,1)) != '00' ) { $title = $id3v1tag['NAME']; } else { $title = explode(DS,$file); $title = $title[count($title)-1]; $title = explode('.',$title); $title=$title[0]; } if (!preg_match('//u', $title)) $title = iconv("cp1251", "UTF-8",$title); } $artist = read_frame ($f, $tagdata, "TPE1"); if (!$artist) { if ($id3v1tag['TAG']== 'TAG' && ascii2hex(substr($id3v1tag['ARTISTS'],0,1)) != '00') { $artist = $id3v1tag['ARTISTS']; } else { $artist = ""; } } if (!preg_match('//u', $artist)) $artist = iconv("cp1251", "UTF-8//TRANSLIT",$artist); $id3tag['NAME'] = $title; $id3tag['ARTIST'] = $artist; return $id3tag; } if (DS == "/") $dir = str_replace("\\",DS,$music_dir); else $dir = str_replace("/",DS,$music_dir); $dir = JPATH_ROOT.DS.$dir; if (!is_dir($dir)) { echo "Wrong dir in settings"; } else { $files = glob($dir.DS."*.{mp3,MP3}",GLOB_BRACE); if (count($files) > 0) { sort($files); $host = $base_uri; foreach ($files as $file) { $tags = readmp3tag($file); $file = explode (DS, $file); if ($server_utf8 == 1) { $fname = rawurlencode($file[count($file)-1]); } else { $fname = rawurlencode($file[count($file)-1]); } $fname = substr($fname, 0, -4); $file = $host."/".$music_dir."/psp.php?name=".$fname; echo $file; $artist = trim($tags['ARTIST']); $artist = $artist == "" ? "" : "{$tags['ARTIST']} - "; $playlist[] = '{name:"'.$artist.$tags['NAME'].'",mp3:"'.$file.'"}'; } } /* * //if(!window.jQuery) { document.write(unescape('<script type="text/javascript" src="<?=$base_uri?>/modules/mod_jlplayer/js/jq.js">%3C/script%3E')); document.write(unescape('<script type="text/javascript">jQuery.noConflict();%3C/script%3E')); //} * */ ?> <script type="text/javascript"> var myPlayList = [ <?php echo implode(",\n ",$playlist)."\n"; ?> ]; Array.prototype.find=function(v){ for (i=0;i<this.length;i++){ if (this[i]==v) return i; } return 0; } var plIndex = []; for (i=0;i<myPlayList.length;i++) { plIndex[i] = i; } <?php if ($shfl == 1) : ?> //shuffle function randOrd(){ return (Math.round(Math.random())-0.5); } plIndex.sort(randOrd); <?php endif; ?> function setCookie (name, value) { document.cookie = name + "=" + escape(value) + "; expires=Thu, 01-Jan-2055 00:00:01 GMT; path=/"; } function getCookie(name) { var cookie = " " + document.cookie; var search = " " + name + "="; var setStr = null; var offset = 0; var end = 0; if (cookie.length > 0) { offset = cookie.indexOf(search); if (offset != -1) { offset += search.length; end = cookie.indexOf(";", offset) if (end == -1) { end = cookie.length; } setStr = unescape(cookie.substring(offset, end)); } } return(setStr); } function changeShflStatus(el) { nowPlay = plIndex[playItem]; if (el.checked) { setCookie("jlp_shfl","shuffle"); plIndex.sort(randOrd); } else { setCookie("jlp_shfl","notshuffle"); plIndex.sort(); } playItem = plIndex.find(nowPlay); } </script> <script type="text/javascript" src="<?=$base_uri?>/modules/mod_jlplayer/js/jq.js"></script> <script type="text/javascript">jQuery.noConflict();</script> <link href="<?=$base_uri?>/modules/mod_jlplayer/skin/skin.css" rel="stylesheet" type="text/css" /> <script type="text/javascript" src="<?=$base_uri?>/modules/mod_jlplayer/js/jquery.jplayer.min.js"></script> <script type="text/javascript"> var playItem = 0; jQuery(function(){ var jpPlayTime = jQuery("#jplayer_play_time"); var jpTotalTime = jQuery("#jplayer_total_time"); var jlp_shfl = getCookie("jlp_shfl"); if (jlp_shfl == "shuffle") { document.getElementById('jlp_shfl').checked = true; } else if (jlp_shfl == "notshuffle") { document.getElementById('jlp_shfl').checked = false; } jsuri = baseuri+"/modules/mod_jlplayer/js/"; jQuery("#jquery_jplayer").jPlayer({ ready: function() { displayPlayList(); playListInit(enable_autoplay); // Parameter is a boolean for autoplay. }, errorAlerts:true, warningAlerts:true, swfPath: jsuri }) .jPlayer("onProgressChange", function(loadPercent, playedPercentRelative, playedPercentAbsolute, playedTime, totalTime) { jpPlayTime.text(jQuery.jPlayer.convertTime(playedTime)); jpTotalTime.text(jQuery.jPlayer.convertTime(totalTime)); }) .jPlayer("onSoundComplete", function() { playListNext(); }); jQuery("#jplayer_previous").click( function() { playListPrev(); return false; }); jQuery("#jplayer_next").click( function() { playListNext(); return false; }); }); function displayPlayList() { for (i=0; i < myPlayList.length; i++) { jQuery("#jplayer_playlist").append("<div id='jplayer_playlist_item_"+i+"'>"+ myPlayList[i].name +"</div>"); jQuery("#jplayer_playlist_item_"+i).data( "index", i ).click( function() { var index = jQuery(this).data("index"); if (plIndex[playItem] != index) { _index = plIndex.find(index); playListChange( _index, index ); } else { jQuery("#jquery_jplayer").jPlayer("play"); } }); } } function playListInit(autoplay) { if(autoplay) { playListChange(0, plIndex[0] ); } else { playListConfig(0, plIndex[0] ); } } function playListConfig(_index, index ) { jQuery("#jplayer_playlist_item_"+plIndex[playItem]).removeClass("jplayer_playlist_current"); jQuery("#jplayer_playlist_item_"+index).addClass("jplayer_playlist_current"); playItem = _index; jQuery("#jquery_jplayer").jPlayer("setFile", myPlayList[plIndex[playItem]].mp3); } function playListChange(_index, index ) { playListConfig(_index, index ); jQuery("#jquery_jplayer").jPlayer("play"); } function playListNext() { var _index = (playItem+1 < myPlayList.length) ? playItem+1 : 0; var index = plIndex[_index]; playListChange(_index, index ); } function playListPrev() { var _index = (playItem-1 >= 0) ? playItem-1 : myPlayList.length-1; var index = plIndex[_index]; playListChange(_index, index ); } </script> <?php include_once(JPATH_ROOT.DS.'modules/mod_jlplayer/skin/tpl.php'); ?> <?php }I was messing around in there with $file if ($server_utf8 == 1) { $fname = rawurlencode($file[count($file)-1]); } else { $fname = rawurlencode($file[count($file)-1]); } $fname = substr($fname, 0, -4); $file = $host."/".$music_dir."/psp.php?name=".$fname; echo $file;I am unsure how to retreive a file title only, with out the whole path, just the name and not even the file ext. It comes up with all the files names in the echo. Also I am not sure how joomline chooses just one file. I am not a php designer and I am quite confused lol Any help would be appreciated! Thank you. when PHPSESSID is stored in a cookie(or URL), and if some hacker gets hold of this wrongfully, can he create a pseudo-authentication, now that he has a sessionid? and then proceed with what a genuine login can do?... how to solve this? Hi everyone! I have a question that might sound silly... I have stored in my database a url to a pic and some other data. I am unsure if when I retreive data from my database I need some sort of protection. I usually sanitize and prevent SQl injections when I code forms but I am not sure if I have to do the same when I get data from the database. Thanks for your help. Veronica |