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From: Ashley Sheridan on 7 Jun 2010 13:45 On Mon, 2010-06-07 at 10:38 -0700, Michael Shadle wrote: > It's not that bad. > > Use filter functions and sanity checks for input. > > Use htmlspecialchars() basically on output. > > That should take care of basically everything. > > On Jun 7, 2010, at 6:16 AM, Igor Escobar <titiolinkin(a)gmail.com> wrote: > > > This was my fear. > > > > Regards, > > Igor Escobar > > Systems Analyst & Interface Designer > > > > + http://blog.igorescobar.com > > + http://www.igorescobar.com > > + @igorescobar (twitter) > > > > > > > > > > > > On Mon, Jun 7, 2010 at 10:05 AM, Peter Lind <peter.e.lind(a)gmail.com> > > wrote: > > > >> On 7 June 2010 14:54, Igor Escobar <titiolinkin(a)gmail.com> wrote: > >>> Hi Folks! > >>> > >>> The portal for which I work is suffering constant attacks that I > >>> feel > >> that > >>> is PHP Injection. Somehow the hacker is getting to change the > >>> cache files > >>> that our system generates. Concatenating the HTML file with > >>> another that > >>> have an iframe to a malicious JAR file. Do you have any > >>> suggestions to > >>> prevent this action? The hacker has no access to our file system, > >>> he is > >>> imputing the code through some security hole. The problem is that > >>> the > >> portal > >>> is very big and has lots and lots partners hosted on our estructure > >>> structure. We are failing to identify the focus of this attacks. > >>> > >>> Any ideas? > >>> > >> > >> Check all user input + upload: make sure that whatever comes from the > >> user is validated. Then check all output: make sure that everythin > >> output is escaped properly. Yes, it's an enormous task, but there's > >> no > >> way around it. > >> > >> Regards > >> Peter > >> > >> -- > >> <hype> > >> WWW: http://plphp.dk / http://plind.dk > >> LinkedIn: http://www.linkedin.com/in/plind > >> BeWelcome/Couchsurfing: Fake51 > >> Twitter: http://twitter.com/kafe15 > >> </hype> > >> > htmlspecialchars() is really only good for user input that you are outputting to the browser. For inserting data into a database, use mysql_real_escape_string(). I find it's good to think carefully about what sort of data I expect and sanitise it accordingly. If I want a numerical value, I use intval($_GET['var']) or floatval(). For things like small text box elements, regex's work well depending on the data. For data from select lists of checkboxes, make sure the value given is within a list of pre-determined values you have. Basically, nothing from the user should be trusted at all, ever. As soon as you let go of that trust in the good honesty of people you'll do fine ;) Thanks, Ash http://www.ashleysheridan.co.uk
From: Michael Shadle on 7 Jun 2010 13:48 Oh yeah. I do more than just intval() I make sure they didn't feed me anything BUT numeric text first. I do sanity check before type forcing :) I use garbage in garbage out. So I take what is given to me and yes I escape if before the db of course as well, and then encode on output. On Jun 7, 2010, at 10:45 AM, Ashley Sheridan <ash(a)ashleysheridan.co.uk> wrote: > On Mon, 2010-06-07 at 10:38 -0700, Michael Shadle wrote: >> >> It's not that bad. >> >> Use filter functions and sanity checks for input. >> >> Use htmlspecialchars() basically on output. >> >> That should take care of basically everything. >> >> On Jun 7, 2010, at 6:16 AM, Igor Escobar <titiolinkin(a)gmail.com> >> wrote: >> >> > This was my fear. >> > >> > Regards, >> > Igor Escobar >> > Systems Analyst & Interface Designer >> > >> > + http://blog.igorescobar.com >> > + http://www.igorescobar.com >> > + @igorescobar (twitter) >> > >> > >> > >> > >> > >> > On Mon, Jun 7, 2010 at 10:05 AM, Peter Lind >> <peter.e.lind(a)gmail.com> >> > wrote: >> > >> >> On 7 June 2010 14:54, Igor Escobar <titiolinkin(a)gmail.com> wrote: >> >>> Hi Folks! >> >>> >> >>> The portal for which I work is suffering constant attacks that I >> >>> feel >> >> that >> >>> is PHP Injection. Somehow the hacker is getting to change the >> >>> cache files >> >>> that our system generates. Concatenating the HTML file with >> >>> another that >> >>> have an iframe to a malicious JAR file. Do you have any >> >>> suggestions to >> >>> prevent this action? The hacker has no access to our file system, >> >>> he is >> >>> imputing the code through some security hole. The problem is that >> >>> the >> >> portal >> >>> is very big and has lots and lots partners hosted on our >> estructure >> >>> structure. We are failing to identify the focus of this attacks. >> >>> >> >>> Any ideas? >> >>> >> >> >> >> Check all user input + upload: make sure that whatever comes >> from the >> >> user is validated. Then check all output: make sure that everythin >> >> output is escaped properly. Yes, it's an enormous task, but >> there's >> >> no >> >> way around it. >> >> >> >> Regards >> >> Peter >> >> >> >> -- >> >> <hype> >> >> WWW: http://plphp.dk / http://plind.dk >> >> LinkedIn: http://www.linkedin.com/in/plind >> >> BeWelcome/Couchsurfing: Fake51 >> >> Twitter: http://twitter.com/kafe15 >> >> </hype> >> >> >> > > htmlspecialchars() is really only good for user input that you are > outputting to the browser. For inserting data into a database, use > mysql_real_escape_string(). I find it's good to think carefully > about what sort of data I expect and sanitise it accordingly. If I > want a numerical value, I use intval($_GET['var']) or floatval(). > For things like small text box elements, regex's work well depending > on the data. For data from select lists of checkboxes, make sure the > value given is within a list of pre-determined values you have. > Basically, nothing from the user should be trusted at all, ever. > > As soon as you let go of that trust in the good honesty of people > you'll do fine ;) > > Thanks, > Ash > http://www.ashleysheridan.co.uk > >
From: Ashley Sheridan on 7 Jun 2010 13:48 On Mon, 2010-06-07 at 14:42 -0300, Igor Escobar wrote: > It's not a SQL Injection or XSS problem, Michael. > > It's a PHP Injection problem. I know how fix that but the web site is very > very huge, have lots and lots of partners and i'm have a bug difficult do > identify the focus of the problem. > > Got it? > > > Regards, > Igor Escobar > Systems Analyst & Interface Designer > > + http://blog.igorescobar.com > + http://www.igorescobar.com > + @igorescobar (twitter) > > > > > > On Mon, Jun 7, 2010 at 2:38 PM, Michael Shadle <mike503(a)gmail.com> wrote: > > > It's not that bad. > > > > Use filter functions and sanity checks for input. > > > > Use htmlspecialchars() basically on output. > > > > That should take care of basically everything. > > > > > > On Jun 7, 2010, at 6:16 AM, Igor Escobar <titiolinkin(a)gmail.com> wrote: > > > > This was my fear. > >> > >> Regards, > >> Igor Escobar > >> Systems Analyst & Interface Designer > >> > >> + http://blog.igorescobar.com > >> + http://www.igorescobar.com > >> + @igorescobar (twitter) > >> > >> > >> > >> > >> > >> On Mon, Jun 7, 2010 at 10:05 AM, Peter Lind <peter.e.lind(a)gmail.com> > >> wrote: > >> > >> On 7 June 2010 14:54, Igor Escobar <titiolinkin(a)gmail.com> wrote: > >>> > >>>> Hi Folks! > >>>> > >>>> The portal for which I work is suffering constant attacks that I feel > >>>> > >>> that > >>> > >>>> is PHP Injection. Somehow the hacker is getting to change the cache > >>>> files > >>>> that our system generates. Concatenating the HTML file with another that > >>>> have an iframe to a malicious JAR file. Do you have any suggestions to > >>>> prevent this action? The hacker has no access to our file system, he is > >>>> imputing the code through some security hole. The problem is that the > >>>> > >>> portal > >>> > >>>> is very big and has lots and lots partners hosted on our estructure > >>>> structure. We are failing to identify the focus of this attacks. > >>>> > >>>> Any ideas? > >>>> > >>>> > >>> Check all user input + upload: make sure that whatever comes from the > >>> user is validated. Then check all output: make sure that everythin > >>> output is escaped properly. Yes, it's an enormous task, but there's no > >>> way around it. > >>> > >>> Regards > >>> Peter > >>> > >>> -- > >>> <hype> > >>> WWW: http://plphp.dk / http://plind.dk > >>> LinkedIn: http://www.linkedin.com/in/plind > >>> BeWelcome/Couchsurfing: Fake51 > >>> Twitter: http://twitter.com/kafe15 > >>> </hype> > >>> > >>> > > -- > > PHP General Mailing List (http://www.php.net/) > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > What do you mean it's a PHP injection? PHP is all on the server, and the only way to get at that if you don't have direct access to the server (which you've said isn't possible as the passwords, etc are all fine) then the bad data is coming from either a form or another area where user data is expected. This data might be as simple as unsanitised URL variables that are intended to fetch a blog entry, to form data sent in a registration page. All data coming from the user is bad until proven otherwise. Thanks, Ash http://www.ashleysheridan.co.uk
From: Ashley Sheridan on 7 Jun 2010 13:51 On Mon, 2010-06-07 at 10:48 -0700, Michael Shadle wrote: > Oh yeah. I do more than just intval() I make sure they didn't feed me > anything BUT numeric text first. I do sanity check before type > forcing :) > > I use garbage in garbage out. So I take what is given to me and yes I > escape if before the db of course as well, and then encode on output. > > On Jun 7, 2010, at 10:45 AM, Ashley Sheridan > <ash(a)ashleysheridan.co.uk> wrote: > > > On Mon, 2010-06-07 at 10:38 -0700, Michael Shadle wrote: > >> > >> It's not that bad. > >> > >> Use filter functions and sanity checks for input. > >> > >> Use htmlspecialchars() basically on output. > >> > >> That should take care of basically everything. > >> > >> On Jun 7, 2010, at 6:16 AM, Igor Escobar <titiolinkin(a)gmail.com> > >> wrote: > >> > >> > This was my fear. > >> > > >> > Regards, > >> > Igor Escobar > >> > Systems Analyst & Interface Designer > >> > > >> > + http://blog.igorescobar.com > >> > + http://www.igorescobar.com > >> > + @igorescobar (twitter) > >> > > >> > > >> > > >> > > >> > > >> > On Mon, Jun 7, 2010 at 10:05 AM, Peter Lind > >> <peter.e.lind(a)gmail.com> > >> > wrote: > >> > > >> >> On 7 June 2010 14:54, Igor Escobar <titiolinkin(a)gmail.com> wrote: > >> >>> Hi Folks! > >> >>> > >> >>> The portal for which I work is suffering constant attacks that I > >> >>> feel > >> >> that > >> >>> is PHP Injection. Somehow the hacker is getting to change the > >> >>> cache files > >> >>> that our system generates. Concatenating the HTML file with > >> >>> another that > >> >>> have an iframe to a malicious JAR file. Do you have any > >> >>> suggestions to > >> >>> prevent this action? The hacker has no access to our file system, > >> >>> he is > >> >>> imputing the code through some security hole. The problem is that > >> >>> the > >> >> portal > >> >>> is very big and has lots and lots partners hosted on our > >> estructure > >> >>> structure. We are failing to identify the focus of this attacks. > >> >>> > >> >>> Any ideas? > >> >>> > >> >> > >> >> Check all user input + upload: make sure that whatever comes > >> from the > >> >> user is validated. Then check all output: make sure that everythin > >> >> output is escaped properly. Yes, it's an enormous task, but > >> there's > >> >> no > >> >> way around it. > >> >> > >> >> Regards > >> >> Peter > >> >> > >> >> -- > >> >> <hype> > >> >> WWW: http://plphp.dk / http://plind.dk > >> >> LinkedIn: http://www.linkedin.com/in/plind > >> >> BeWelcome/Couchsurfing: Fake51 > >> >> Twitter: http://twitter.com/kafe15 > >> >> </hype> > >> >> > >> > > > > htmlspecialchars() is really only good for user input that you are > > outputting to the browser. For inserting data into a database, use > > mysql_real_escape_string(). I find it's good to think carefully > > about what sort of data I expect and sanitise it accordingly. If I > > want a numerical value, I use intval($_GET['var']) or floatval(). > > For things like small text box elements, regex's work well depending > > on the data. For data from select lists of checkboxes, make sure the > > value given is within a list of pre-determined values you have. > > Basically, nothing from the user should be trusted at all, ever. > > > > As soon as you let go of that trust in the good honesty of people > > you'll do fine ;) > > > > Thanks, > > Ash > > http://www.ashleysheridan.co.uk > > > > Why waste time validating an integer value when intval() will do that for you? Thanks, Ash http://www.ashleysheridan.co.uk
From: Igor Escobar on 7 Jun 2010 13:52
I think we're getting off topic here folks... Regards, Igor Escobar Systems Analyst & Interface Designer + http://blog.igorescobar.com + http://www.igorescobar.com + @igorescobar (twitter) On Mon, Jun 7, 2010 at 2:51 PM, Ashley Sheridan <ash(a)ashleysheridan.co.uk>wrote: > On Mon, 2010-06-07 at 10:48 -0700, Michael Shadle wrote: > > Oh yeah. I do more than just intval() I make sure they didn't feed me > anything BUT numeric text first. I do sanity check before type > forcing :) > > I use garbage in garbage out. So I take what is given to me and yes I > escape if before the db of course as well, and then encode on output. > > On Jun 7, 2010, at 10:45 AM, Ashley Sheridan > <ash(a)ashleysheridan.co.uk> wrote: > > > On Mon, 2010-06-07 at 10:38 -0700, Michael Shadle wrote: > >> > >> It's not that bad. > >> > >> Use filter functions and sanity checks for input. > >> > >> Use htmlspecialchars() basically on output. > >> > >> That should take care of basically everything. > >> > >> On Jun 7, 2010, at 6:16 AM, Igor Escobar <titiolinkin(a)gmail.com> > >> wrote: > >> > >> > This was my fear. > >> > > >> > Regards, > >> > Igor Escobar > >> > Systems Analyst & Interface Designer > >> > > >> > + http://blog.igorescobar.com > >> > + http://www.igorescobar.com > >> > + @igorescobar (twitter) > >> > > >> > > >> > > >> > > >> > > >> > On Mon, Jun 7, 2010 at 10:05 AM, Peter Lind > >> <peter.e.lind(a)gmail.com> > >> > wrote: > >> > > >> >> On 7 June 2010 14:54, Igor Escobar <titiolinkin(a)gmail.com> wrote: > >> >>> Hi Folks! > >> >>> > >> >>> The portal for which I work is suffering constant attacks that I > >> >>> feel > >> >> that > >> >>> is PHP Injection. Somehow the hacker is getting to change the > >> >>> cache files > >> >>> that our system generates. Concatenating the HTML file with > >> >>> another that > >> >>> have an iframe to a malicious JAR file. Do you have any > >> >>> suggestions to > >> >>> prevent this action? The hacker has no access to our file system, > >> >>> he is > >> >>> imputing the code through some security hole. The problem is that > >> >>> the > >> >> portal > >> >>> is very big and has lots and lots partners hosted on our > >> estructure > >> >>> structure. We are failing to identify the focus of this attacks. > >> >>> > >> >>> Any ideas? > >> >>> > >> >> > >> >> Check all user input + upload: make sure that whatever comes > >> from the > >> >> user is validated. Then check all output: make sure that everythin > >> >> output is escaped properly. Yes, it's an enormous task, but > >> there's > >> >> no > >> >> way around it. > >> >> > >> >> Regards > >> >> Peter > >> >> > >> >> -- > >> >> <hype> > >> >> WWW: http://plphp.dk / http://plind.dk > >> >> LinkedIn: http://www.linkedin.com/in/plind > >> >> BeWelcome/Couchsurfing: Fake51 > >> >> Twitter: http://twitter.com/kafe15 > >> >> </hype> > >> >> > >> > > > > htmlspecialchars() is really only good for user input that you are > > outputting to the browser. For inserting data into a database, use > > mysql_real_escape_string(). I find it's good to think carefully > > about what sort of data I expect and sanitise it accordingly. If I > > want a numerical value, I use intval($_GET['var']) or floatval(). > > For things like small text box elements, regex's work well depending > > on the data. For data from select lists of checkboxes, make sure the > > value given is within a list of pre-determined values you have. > > Basically, nothing from the user should be trusted at all, ever. > > > > As soon as you let go of that trust in the good honesty of people > > you'll do fine ;) > > > > Thanks, > > Ash > > http://www.ashleysheridan.co.uk > > > > > > > Why waste time validating an integer value when intval() will do that for > you? > > > Thanks, > Ash > http://www.ashleysheridan.co.uk > > > |