On 30 Jul 2015, at 17:02, Joe Watkins <[email protected]> wrote:
> Even if some of those people replying haven't read or don't understand what you are
> suggesting, it is not a good tactic to assume that and reply with "read the RFC".
Hi Joe,
Sorry about yesterday, I have done as you have said, and I have read those responses again, but
unfortunately I still feel that I was right in my assumptions (notes below, maybe some interesting
additions?).
In general I have been getting very frustrated that no-one seems to really care about security (and
to be fair, it has been annoying me for far too many years).
Keeping in mind that I work with other developers who routinely keep introducing vulnerabilities
like SQLi, XSS, CSRF... and doing annoying things like switching the CSP off, because they
copy/paste some hideous/insecure JS, and can't be bothered to work out why the "eval"
function isn't working.
So maybe I should start a new thread, without Matt's subject (btw Matt, I really appreciate
what you are trying todo, I disagree with the blocking element, and I think we can also address more
than just SQL injection vulnerabilities)... maybe something like "I've found this one
weird trick that will fix every security issue"... sorry, I hate that kind of approach, but if
it gets a response, maybe its worth it :-)
Craig
--------------------------------------------------
http://news.php.net/php.internals/87346
From: Matt Tait
Reply: N/A
Original suggestion.
--------------------------------------------------
http://news.php.net/php.internals/87348
From: Rowan Collins
Reply: Matt Tait
Suggestion to Matt to look for previous RFCs.
--------------------------------------------------
http://news.php.net/php.internals/87350
From: Christoph Becker
Reply: Matt Tait
Points out the existing Taint RFC from 2008, by Wietse Venema.
--------------------------------------------------
http://news.php.net/php.internals/87355
From: Pierre Joye
Reply: Matt Tait
Pointing out that there is more than SQLi (true), and it might be an impossible task (I disagree, as
explained later).
--------------------------------------------------
http://news.php.net/php.internals/87361
From: Thomas Bley
Reply: Matt Tait
Suggesting the use of bound parameters / prepared statements, which I agree is how it should be
coded by the website developers, but I think the PHP language itself can help identify when this has
not been done (just by raising a notice, not blocking anything).
Also Thomas points out that static code analysis could identify these issues, but these are far from
perfect, and PHP is in a much better position to be doing this... and has the advantage of being
available to everyone.
Just to note, I've played with a couple of static code analysers which cost in the region of
£19,000 per year, and they still don't find the same number of escaping issues that my
suggestion can find (they do look at other issues, so don't get rid of them, but this one thing
that can be done better with the programming language itself).
--------------------------------------------------
http://news.php.net/php.internals/87363
From: Lester Caine
Reply: Matt Tait
Short answer saying you should not use mysql... which I think is a bit short sighted (on the
assumption that mysqli is a similar interface for most website developers).
I'm not against using tools like ORMs (e.g. Doctrine), bound parameters / prepared statements,
or even stored procedures... but they all have issues, and are all vulnerable to the kind of misuse
I'm trying to address (explained in the next email).
--------------------------------------------------
http://news.php.net/php.internals/87370
From: Me (Craig Francis)
Reply: Lester Caine
Just saying I disagree with Lester, and giving a very simple example of how developers can still
mess up (once you start adding some abstractions, like an ORM, this becomes much harder to detect,
and is why I'm so insistent that PHP needs to be checking for these issues).
This is where I also suggest an alternative to Matt's original suggestion (something I posted
12 days before, and didn't really get any response).
--------------------------------------------------
http://news.php.net/php.internals/87383
From: Lester Caine
Reply: Me (Craig Francis)
Kind of missing the point (maybe my example was too simple), and is talking about how Matts solution
would cause problems.
And I agree (sorry Matt), I don't think Matt's solution would work... but if Lester had
read my reply, he would have seen that my suggestion was about education (but it can also help
experienced developers as well).
--------------------------------------------------
http://news.php.net/php.internals/87386
From: Me (Craig Francis)
Reply: Lester Caine
Trying to explain to Lester that I agree on education, and pointing out that my solution is
different... and how (maybe my email was too long to read?).
--------------------------------------------------
http://news.php.net/php.internals/87391
From: Joe Watkins
Reply: Me (Craig Francis)
Saying you agree with Pierre... I do as well, as Pierre was talking about Matt's solution.
--------------------------------------------------
http://news.php.net/php.internals/87393
From: Me (Craig Francis)
Reply: Joe Watkins
Pointing out that my suggestion was different... I realise I'm now trying to derail Matt's
original thread (this one seems to be getting some attention), but I really want to address these
same issues.
--------------------------------------------------
http://news.php.net/php.internals/87396
From: Xinchen Hui
Reply: Joe Watkins
Giving a quick status update on the original 2008 implementation... which I personally think is
good, but could be made better by switching the logic around (I believe this will make the
implementation easier, and avoid many edge cases).
--------------------------------------------------
http://news.php.net/php.internals/87400
From: Scott Arciszewski
Reply: Matt Tait
Pointing out that Cross-Site Scripting is a bigger issue now... where I think that taints can
address both issues (and more).
He also says that prepared statements is a solved problem (something that I partially disagree with,
and have explained above, but I realise that Scott is replying to Matt's original email, so may
not have read that far yet).
--------------------------------------------------
http://news.php.net/php.internals/87403
From: Me (Craig Francis)
Reply: Xinchen Hui
Just saying that I appreciate the work Xinchen is doing, and offering to help (assuming I can)... I
do also go off on a bit of a tangent, as I think that if we invert the 2008 RFC to mark things when
they are escaped (rather than tainting everything as they are created), then I think the
implementation would be a lot easier.
--------------------------------------------------
http://news.php.net/php.internals/87404
From: Me (Craig Francis)
Reply: Scott Arciszewski
Pointing out that I have a different suggestion.
I also wanted to say that I don't think SQL injection is a solved problem, as I tried to
explain earlier (which Scott may not have read yet)... but I certainly didn't want Scott to
just sit back and think everything is solved now, so no need to discuss.
--------------------------------------------------
http://news.php.net/php.internals/87405
From: Scott Arciszewski
Reply: Me (Craig Francis)
Skipping over my suggestion, and just saying that education is needed... which is what I'm also
trying to do.
But as PHP is the only thing that can be forced in front of a new developer, it is really the only
common thing that can do that education (there is no way you can find and talk to every single new
developer just by answering questions on Stack Overflow).
And just as an example, college students leaning to write C programs in 2015 and creating buffer
overflow vulnerabilities... they still make mistakes (even highly experienced developers still make
these mistakes)... and you also have to recognise that not every programmer will go to a college,
and that not all colleges actually teach their students about this (unfortunately).
--------------------------------------------------
http://news.php.net/php.internals/87406
From: Ronald Chmara
Reply: ???
I'm going to assume this is a reply to Matt's suggestion (or just the subject).
And I agree, that suggestion would break every single application... hence why I'm not
suggesting that approach.
--------------------------------------------------
http://news.php.net/php.internals/87407
From: Me (Craig Francis)
Reply: Ronald Chmara
I'm just explaining that I've hijacked the email thread started by Matt, and that there is
more to the discussion.
--------------------------------------------------
http://news.php.net/php.internals/87408
From: Me (Craig Francis)
Reply: Scott Arciszewski
I am getting a little frustrated, and just want to move the discussion on.
Unfortunately what you don't know is that I've been having this issue for too many years,
and I'm getting quite annoyed that we aren't addressing these problems in a simple way.
Instead, what I keep seeing is more complicated half solutions (e.g. ORMs and query builders, where
typical website developers have no idea what the SQL/DB is doing, so vulnerabilities still creep in,
and introduce other problems like n+1).
The amount of times I've been to PHP conferences where the speaker is explaining some new way
that they are doing OOP (or maybe even functional programming), and I'm sure they are really
proud of their highly complex solution that few people in the audience understand (and no, I'm
usually able to follow along, my experience is trying to explain what the talk was about to another
audience member afterwards).
But ultimately they haven't addressed anything todo with security, and it is often less
performant (typical response "hey, get a faster computer"), it has instead taken them 3+
months to implement, has resulted in another 1 or 2 layers of abstraction that the typical developer
does not understand (they just run it, and hope for the best).
Then in 6 months time they will have moved on to a different complex solution, and can't be
bothered to support the old one any more (because they just want something hard/complex to work on?
I'm assuming it's an ego thing?).
--------------------------------------------------
http://news.php.net/php.internals/87409
From: Joe Watkins
Reply: Me (Craig Francis)
Where we are today... where you are talking about the RFC (from 2008, or the one from Matt), not
what I've just said about my suggestion (which, if you haven't read, is different).
--------------------------------------------------
On 30 Jul 2015, at 17:02, Joe Watkins <[email protected]> wrote:
> Even if some of those people replying haven't read or don't understand what you are
> suggesting, it is not a good tactic to assume that and reply with "read the RFC".
>
> There is a good chance the majority of the people replying have read the RFC, and found reason
> to be negative, reserved, cautious, or whatever.
>
> The best thing you can do now is read those responses again, and try to find what they are
> saying, if you want the conversation to continue.
>
> Cheers
> Joe
>
> On Thu, Jul 30, 2015 at 4:38 PM, Craig Francis <[email protected]> wrote:
> On 30 Jul 2015, at 16:24, Scott Arciszewski <[email protected]> wrote:
>
> > Just because the solution is known doesn't mean it's known to everyone.
>
>
>
> Yes, and if you could just read what I was suggesting, rather than looking at the subject of
> this email (and the suggestion by Matt), then you will notice this is what I'm trying to do (so
> not just people asking questions on Stack Overflow).
>
> My suggestion is to educate, it also has a nice side effect of having a simple checking process
> for everything else (without breaking anything).
>
>
>
>
>
>
>
>
>
> On 30 Jul 2015, at 16:24, Scott Arciszewski <[email protected]> wrote:
>
> > On Thu, Jul 30, 2015 at 11:20 AM, Craig Francis
> > <[email protected]> wrote:
> >> On 30 Jul 2015, at 14:43, Scott Arciszewski <[email protected]> wrote:
> >>
> >>> This may have been true at one point in time, but my own experience
> >>> and the statistics collected by Dan Kaminsky of White Hat Security
> >>> indicates that Cross-Site Scripting vulnerabilities are much more
> >>> prevalent in 2015 than SQL Injection, especially in business
> >>> applications.
> >>
> >>
> >> Good, because my suggestion was also addressing XSS with poor (or completely missing)
> >> HTML escaping... have a look:
> >>
> >> http://news.php.net/php.internals/87207
> >>
> >> https://bugs.php.net/bug.php?id=69886
> >>
> >> Now I admit it won't fix everything with XSS (as HTML escaping is a bit harder),
> >> but it certainly will pick up quite a lot of the issues (and it wont break anything either, just
> >> help developers identify problems).
> >>
> >> And no, SQL injection is far from a solved problem... this is why, after 15 years of
> >> me trying to tell my fellow developers to not make these mistakes, I'm still finding them
> >> making them over and over again... hence why I'm making the above suggestion.
> >>
> >> Craig
> >>
> >>
> >>
> >>
> >>
> >>
> >> On 30 Jul 2015, at 14:43, Scott Arciszewski <[email protected]> wrote:
> >>
> >>> On Tue, Jul 28, 2015 at 1:33 PM, Matt Tait <[email protected]> wrote:
> >>>> Hi all,
> >>>>
> >>>> I've written an RFC (and PoC) about automatic detection and blocking of
> >>>> SQL
> >>>> injection vulnerabilities directly from inside PHP via automated taint
> >>>> analysis.
> >>>>
> >>>> https://wiki.php.net/rfc/sql_injection_protection
> >>>>
> >>>> In short, we make zend_strings track where their value originated. If it
> >>>> originated as a T_STRING, from a primitive (like int) promotion, or as a
> >>>> concatenation of such strings, it's query that can't have been
> >>>> SQL-injected
> >>>> by an attacker controlled string. If we can't prove that the query is
> >>>> safe,
> >>>> that means that the query is either certainly vulnerable to a SQL-injection
> >>>> vulnerability, or sufficiently complex that it should be parameterized
> >>>> just-to-be-sure.
> >>>>
> >>>> There's also a working proof of concept over here:
> >>>>
> >>>> http://phpoops.cloudapp.net/oops.php
> >>>>
> >>>> You'll notice that the page makes a large number of SQL statements, most
> >>>> of
> >>>> which are not vulnerable to SQL injection, but one is. The proof of concept
> >>>> is smart enough to block that one vulnerable request, and leave all of the
> >>>> others unchanged.
> >>>>
> >>>> In terms of performance, the cost here is negligible. This is just basic
> >>>> variable taint analysis under the hood, (not an up-front intraprocedurale
> >>>> static analysis or anything complex) so there's basically no slow down.
> >>>>
> >>>> PHP SQL injections are the #1 way PHP applications get hacked - and all SQL
> >>>> injections are the result of a developer either not understanding how to
> >>>> prevent SQL injection, or taking a shortcut because it's fewer keystrokes
> >>>> to do it a "feels safe" rather than "is safe" way.
> >>>>
> >>>> What do you all think? There's obviously a bit more work to do; the PoC
> >>>> currently only covers mysqli_query, but I thought this stage is an
> >>>> interesting point to throw it open to comments before working to complete
> >>>> it.
> >>>>
> >>>> Matt
> >>>
> >>> Hi Matt,
> >>>
> >>>> PHP SQL injections are the #1 way PHP applications get hacked - and all SQL
> >>>> injections are the result of a developer either not understanding how to
> >>>> prevent SQL injection, or taking a shortcut because it's fewer keystrokes
> >>>> to do it a "feels safe" rather than "is safe" way.
> >>>
> >>> This may have been true at one point in time, but my own experience
> >>> and the statistics collected by Dan Kaminsky of White Hat Security
> >>> indicates that Cross-Site Scripting vulnerabilities are much more
> >>> prevalent in 2015 than SQL Injection, especially in business
> >>> applications. If Google has information that indicates that SQLi is
> >>> still more prevalent than XSS, I'd love to see this data.
> >>>
> >>> In my opinion, SQL injection is almost a solved problem. Use prepared
> >>> statements where you can, and strictly whitelist where you cannot
> >>> (i.e. "ORDER BY {$column} ASC")
> >>>
> >>> Scott Arciszewski
> >>> Chief Development Officer
> >>> Paragon Initiative Enterprises <https://paragonie.com>
> >>>
> >>> --
> >>> PHP Internals - PHP Runtime Development Mailing List
> >>> To unsubscribe, visit: http://www.php.net/unsub.php
> >>>
> >>
> >
> > Just because the solution is known doesn't mean it's known to
> > everyone. Diffusion of knowledge and good habits is the hardest
> > problem in application security to solve. Look, for example, at how
> > many college students learn to write C programs with buffer overflow
> > vulnerabilities in 2015. We need more effort on education, which is
> > part of what I've been focusing on with Paragon Initiative and Stack
> > Overflow.
> >
> > Scott Arciszewski
> > Chief Development Officer
> > Paragon Initiative Enterprises <https://paragonie.com>
>
>
> --
> PHP Internals - PHP Runtime Development Mailing List
> To unsubscribe, visit: http://www.php.net/unsub.php
>
>