So I've been going through my forms recently to check my SQL queries are secure along with sanitizing any input and have just found that entering <? into a text box triggers a 403 before it even hits the processing file, I can only assume it must be related to mod_security??
My question is, is this something to just not worry about if it's controlled by the web host as I'm using shared hosting.
I recently ran into a problem with submitting form data via a GET request to the server after using jQuery's .serialize() function for the submitted variables. These were web apps that had worked flawlessly for years. It turned out that after a recent ModSecurity rule set update, I was triggering the 211700 (HTTP redirect) and 217280 (smuggling attack) rules in Comodo's WAF ruleset, which the server uses with ModSecurity. I wasn't getting a 403. My IP address got blocked by the firewall. :(
The fix was switching my AJAX code to use to POST instead of GET, and not using .serialize(). I still have some web apps that use .serialize() and GET requests via AJAX without triggering ModSecurity, so I believe it is also necessary to pass suspect characters, as you discovered, though in my testing, all I was using was parentheses.
Since you're on a shared server, it's probably not possible--or worth your time--to find out what rule set the host is using, so your best bet is most likely to switch your form submissions to using POST instead of GET, and not use .serialize(). I figure those rules are there for a reason, and a better approach is to avoid having my code look like it's doing something nefarious than to disable the rules.
I want to use an application that checks for broken links. I got to know that, Xenu is one such software. I do not have access to internal aspx/http files on a drive. The Problem I am facing is the Website requires the user to be authenticated. After login I need to crawl the site to determine which links are broken.
As an example, I kick off with mail.google.com. We end up typing the Username and password after which we are served different URLs. If I give the Xenu (or similar programs) the link such as mail.google.com it will not be able to fecth URLs inside the mail.google.com which will be of type - /mail/u/0/?shva=1#inbox/ etc. There lies the problem.
With minimal or least scripting language how can I provide Xenu (or other similar app) capability to Login by providing external URL (mail.google.com) in this example in order to do whatever xenu has to do.
Thanks
Balaji S
Xenu can be used with an authenticated user as long as the cookies are persistent. You will need to enable cookies in Xenu and login once yourself using IE.
From their FAQ:
By default, cookies are disabled, and Xenu rejects all cookies. If you
need cookies because
you have used Internet Explorer to authenticate yourself before
starting a run
to prevent the server from delivering URLs with a
session ID
then you can enable the cookies in the advanced options
dialog. (This has been available since Version 1.2g)
Warning: You
should not use this option if you have links that delete data, e.g. a
database or a shop - you are risking data loss!!!
You can enable cookies in the Options menu. Click Preferences and switch to the Advanced tab.
For single page applications (like gmail) you will also need to configure Xenu to parse Javascript
This is done by modifying the ini file (traditionally at C:\Program Files (x86)\Xenu135\Xenu.ini) and adding a line of code under [Options]
Javascript=[Jj]ava[Ss]cript: *[_a-zA-Z0-9]+ *\( *['"]((/|ftp://|https?://)[^'"]+)['"]
There are several variations provided in their FAQ, but I didn't get them to work perfectly.
hello all i havent managed to find this elsewhere here nor in the old GAS product forum so here goes:
i am writing a simple client javascript which queries various APIs. when it comes to querying a certain GAS script i have set up to access gmail, i understand i am supposed to serve its data through JSONP. the client script dynamically injects a SCRIPT tag and should normally handle this "response" as script. except whenever the response contains html, requesting the user to grant permissions. in this case this HTML goes into the SCRIPT raising syntax error with MIME type mismatch.
researching this problem i was led to believe the solution lies somewhere around redirecting the user to this page always before every call. so my question is, where can i find best practice regarding this issue?
Unfortunately there isn't a full solution for detecting and granting authorizations to scripts used in JSONP requests. I've seen workarounds where an application first prompts the users to visit the web app's URL, so that they can grant authorization, before allowing them to use the JSONP portion of the application.
I have enabled SSL and I am doing a jQuery AJAX post request and sending some fields to the server.
When I look at the AJAX post request through firebug under the post parameters I see all the fields in clear text.
So this means I can see the passwords in clear text. Is this normal? I am also looking at it with fiddler and it does not even log this AJAX request(so its like the request was never made).
So is it just because firebug is installed in the browser and can capture it or what?
ssl enables security when the data moves from browser to web sever. Firebug is a browser plugin, it knows everything in the DOM tree. I think it makes sense for firebug display the input fields and form data.
Yes, you can see the field data because FireBug is capturing the requests inside Firefox before they're encrypted. If you inspect the actual network traffic with a protocol analyzer like Wireshark you'll see that it's encrypted.
Off the top of my head I would think that Firebug is showing you exactly what is being sent. Otherwise it would mean that it is somehow decode encoded information.
If you really want to confirm this, use a tool which can capture the web traffic outside of the browser. Tcpdump for example.
"So this means I can see the passwords in clear text. Is this normal?"
Yup. The data resides on your browser, that is - the user agent, and is captured before it is communicated to the server. Any encryption operation is vulnerable to sniffing at the point at which the value enters the closed system. That's why if your machine is compromised (say, by malware) very little will help.
I have a login screen which I'm serving over SSL. The user fills in their login/password, this gets POSTed to the server. At this point I want to jump out of SSL, so I redirect them back to the same page with no SSL.
This causes the browser to show a warning dialog "You are about to be redirected to a connection that is not secure". How can I avoid this? I've been plenty of sites like yahoo mail, and gmail that give you an SSL page for login, then send you to a non-SSL page after this.
Secondary question: what's the purpose of this dialog? It's trying to warn me about some nefarous purpose - but what's so bad about redirecting someone to a non-SSL page? I don't get a warning when I'm on an SSL page and click a non-SSL link. What's different about redirecting someone?
I'm doing this in ASP.NET 2.0 - but I figure this is a generic web-dev question.
UPDATE SUMMARY: It seems the popular answer is "DON'T AVOID IT". I can understand that a user should get a message when security it being removed. But I don't get a dialog when I follow a link and security is removed, so at the very least I'd say this is inconsistent.
The dialog / browser versions. I actually don't see the dialog in IE7/FF3 (maybe I've clicked a checkbox preventing it). More importantly the client DOES see it in IE6 - with no checkbox to remove it (yes, I know IE6 is old and crap).
Firefox2: FF2 http://img521.imageshack.us/img521/8455/sslwarning.jpg
IE6:
The alternative: make the entire site SSL, never redirect the user out of SSL. I could handle that. But I've got a semi-technical client who has some fairly good points:
"SSL is going to cause an increase in traffic / processing power". I don't really buy this, and I don't think his site is every going to require more than one box to serve it.
"Yahoo does it. Yahoo is a big technical company. Are you smarter than Yahoo?"
I'm going to try sway the client over to an entirely SSL site. I'll argue Yahoo's approach made sense in 1996, or for a site that is MUCH more popular. Some official links explaining why this dialog happens would help (i.e Jakob Nielsen level of authenticity).
I've hit this same problem a while back. So I had a look inside fiddler to see how yahoo mail does it. Here's the step I saw (and used on my site):
User fills in SSL encrypted form, and POSTs to the server. Server authenticates, and spits out some script to redirect the client
<script language="JavaScript">
<!--
window.location.replace("~~ non-SSL URL ~~");
// -->
</script>
I figure the client side code is there to avoid this dialog.
"How can I avoid this?"
You shouldn't!
Although you could try that with JavaScript. This might work on some browsers and fail on others.
"What's the purpose of this dialog?"
It warns because switching between SSL and non-SSL on websites is usually unexpected by the user. A warning about the "non-SSL to SSL" is not emitted since it increases security and privacy. However, when security is suddenly decreased, the user should notice that quickly, in order to avoid a false feeling of security. In fact, redirecting to a non-SSL site is sometimes used in XSS/MITM attacks.
"SSL is going to cause an increase in traffic / processing power"
This is nonsense. It might be true for sites full of big, static content. However, for normal dynamic web applications, encryption is very cheap compared to business logic, database access, etc.
There is an urban legend saying that SSL-content is not chached by browsers. See "Will web browsers cache content over https" for more information.
"Yahoo does it. Yahoo is a big technical company. Are you smarter than Yahoo?"
Some rhetoric counter-questions:
Are you a big technical company like Yahoo?
Did being a big technical company prevent Microsoft from producing crappy software?
Do you have to support crappy old (SSL-broken) browsers, as Yahoo has to?
The attack this is preventing against is a man-in-the-middle SSL session strip. The message is there with good cause.
As for the purpose: It's to make you aware that your connection won't be SSL encrypted anymore. You may have seen before that the connection is encrypted and may think that it still is, so this warning says "Just to be clear, whatever data you send from here on will be plaintext".
As for how to suppress it: AFAIK you can't, it's a browser thing, what would be the point of the message otherwise? Even though there are workarounds like client-side redirects, I don't think you should try to work around client "problems" like this. If the browser chooses to be verbose, let it. There's a "Don't show this again" checkbox on the dialog after all If the user wishes to suppress this message he can easily do so, and maybe he actually likes to see it.
Also, IMHO, if the browser was worth its salt it would still pop up this warning, even if you employed client-side redirect tricks.
Use SSL for the whole page in the first place!
There's nothing wrong with SSL. You should provide user privacy everywhere, not only on login. It makes sense an the whole site. So simply redirect all non-SSL pages to SSL pages and keep everything SSL.
Just point your client to the latest attacks against mixed mode content (lookup CookieMonster on fscked.org) and proxy attacks (against sites available both in http and https, lookup Pretty-Bad-Proxy). He might reconsider.
It is much easier to get security right if you only deal with one protocol without mixing the two. SSL adds a bit of overhead, but it is nothing compared to the cost of a breach.
Gmail, yahoo, etc. use SSL for an encrypted iframe, which authenticates, but there's none of the in-page redirection you're talking about. The whole page isn't encrypted for these login systems.
read:
http://support.microsoft.com/kb/883740
which says that this is fixed in a hotfix or with a changed registry setting. However, not all the IE6 cpu's we use have this problem, nor do their registry settings correspond to what this article says they should. Also some that give the msg are XPsp3 and IE6 sp3.
We have an https log in screen that uses code to log into 15 other (http) domains and some of our IE6 users have to click 'Yes' 15 times. This is inacceptable to them.
No, we cannot control what browser all our users use. Some are not compatible with upgrade to IE7.
We are looking for some config attribute for each user to adjust that will suppress this msg. We've identically configed a 'bad' browser with settings that match one that does not give the msg. Internet and Intranet Security and Advanced settings and Proxies (none).Also Network connections. No joy so far.
Any ideas?