Entries tagged security
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In what circumstances should one use “magic quotes” in PHP?
Absolutely never. Magic quotes was a badly designed feature, and PHP has been trying to escape its legacy for years. If you are constructing SQL strings using string concatenation you’re asking for trouble—use prepared statements or a library that interpolates and correctly escapes variables for you.
[... 65 words]Django ponies: Proposals for Django 1.2
I’ve decided to step up my involvement in Django development in the run-up to Django 1.2, so I’m currently going through several years worth of accumulated pony requests figuring out which ones are worth advocating for. I’m also ensuring I have the code to back them up—my innocent AutoEscaping proposal a few years ago resulted in an enormous amount of work by Malcolm and I don’t think he’d appreciate a repeat performance.
[... 1674 words]Teaching users to be secure is a shared responsibility
Ryan Janssen: Why an OAuth iframe is a Great Idea.
[... 570 words]Rate limiting with memcached
On Monday, several high profile “celebrity” Twitter accounts started spouting nonsense, the victims of stolen passwords. Wired has the full story—someone ran a dictionary attack against a Twitter staff member, discovered their password and used Twitter’s admin tools to reset the passwords on the accounts they wanted to steal.
[... 910 words]The point of “Open” in OpenID
TechCrunch report that Microsoft are accepting OpenID for their new HealthVault site, but with a catch: you can only use OpenIDs from two providers: Trustbearer (who offer two-factor authentication using a hardware token) and Verisign. "Whatever happened to the Open in OpenID?", asks TechCrunch’s Jason Kincaid.
[... 451 words]Designing for a security breach
User account breaches are inevitable. We should take that in to account when designing our applications.
[... 545 words]Massive Dreamhost hack, WordPress not to blame
On mezzoblue, Dave Shea reports that someone had modified every index.php and index.html file on his site to include spam links at the bottom of the page, hidden inside a <u style="display: none;">. Dozens of other people in his comments reported the same thing happening to their sites.
Solving the OpenID phishing problem
Most of the arguments I hear against OpenID are based on mis-understandings of the specification, but there is one that can’t be ignored: OpenID is extremely vulnerable to phishing.
[... 531 words]How is Google giving me access to this page?
Google have an open URL redirector, so you can craft a link that uses that:
[... 35 words]Don’t be eval()
JavaScript is an interpreted language, and like so many of its peers it includes the all powerful eval() function. eval() takes a string and executes it as if it were regular JavaScript code. It’s incredibly powerful and incredibly easy to abuse in ways that make your code slower and harder to maintain. As a general rule, if you’re using eval() there’s probably something wrong with your design.
Social engineering and Orange
I had a call on my mobile earlier today from a lady claiming to be from Orange (my phone service provider) who told me that my contract was about to expire. She asked me for my password.
[... 311 words]Understanding the Greasemonkey vulnerability
If you have any version of Greasemonkey installed prior to 0.3.5, which was released a few hours ago, or if you are running any of the 0.4 alphas, you need to go and upgrade right now. All versions of Greasemonkey aside from 0.3.5 contain a nasty security hole, which could enable malicious web sites to read any file from your hard drive without you knowing.
[... 809 words]Fighting RFCs with RFCs
Google’s recently released Web Accelerator apparently has some scary side-effects. It’s been spotted pre-loading links in password-protected applications, which can amount to clicking on every “delete this” link — bypassing even the JavaScript prompt you carefully added to give people the chance to think twice.
[... 353 words]Giving away the index
My final year project is due in two weeks, and I’m going to be running on silent for most of them. I have, however, upgraded to Tiger and playing with Spotlight has given me plenty to think about.
[... 414 words]The Register hit by XSS
Here’s a nasty one: popular tech news site The Register was hit on Saturday by the Bofra exploit, a nasty worm which uses an iframe vulnerability in (you guessed it) Internet Explorer to install nasty things on the victim’s PC. Where it gets interesting is that the attack wasn’t against the Register themselves; it came through their third party ad serving company, Falk AG.
[... 262 words]The bookmarklet solution to the password problem
Anyone who makes heavy use of the internet has run in to the password problem: dozens of user accounts on sites with varying degrees of trustability, leading to an unmanageable proliferation of username and password combinations. The temptation is to use the same combination on multiple sites, but doing so opens you up to the horrifying prospect of a security flaw in one site compromising al of your other accounts.
[... 366 words]Defending against the OS X help: vulnerability
There’s a nasty OS X vulnerability under discussion at the moment which lets a web page execute code on your machine by taking advantage of a flaw in the “help:” protocol. There’s a non-malicious demonstration of the exploit on this page, and Jay Allen is hosting a discussion on the exploit and ways to avoid it.
[... 253 words]It’s only going to get worse
This analysis of the spread of the witty worm is fascinating for a whole bunch of different reasons.
[... 395 words]Bizex
I’m going to try not to turn this in to a blog about Windows security exploits but this one is genuinely interesting in that it actively tries to steal financial information and important passwords. Bizex spreads itself by spamming messages over ICQ advising the recipient to visit a specific URL. When they visit it, Internet Explorer exploits are used to download and execute the main payload which then infects their ICQ program and uses it to message their contacts. The worm also scans their hard drive for information relating to a number of well known financial services which it then uploads to a server via FTP, and it apparently snoops on their browser for any passwords travelling over HTTPS connections as well.
[... 216 words]Novel security measures
An article on SecurityFocus led me to this site about Port Knocking. Port Knocking is an interesting security technique in which a box sits online with no ports open to connections and awaits a specific sequence of connection attempts. A user wishing to connect to the box must first attempt to initiate connections to ports in a specific, secret order. Once they do, the box starts up the required service (such as an SSH daemon) on a designated port and allows the user to connect properly.
[... 145 words]“I’m Brian and so’s my wife”
I’m subscribed to a whole bunch of mailing lists, mostly as a lurker as I have a hard enough time just keeping up with some of them. One of those lists is Bugtraq, which is pretty much required reading for anyone with sysadmin responsibilities for a server connected to the public internet. Bugtraq is the central hub of the “public disclosure” security community and is actually surprisingly low traffic with only twenty or so messages a day. It’s fascinating to watch the latest exploits for all manner of popular software packages tick by on an hourly basis.
[... 285 words]Defending web applications against dictionary attacks
Over at Reflective Surface, Ronaldo M. Ferraz discusses the usability of an authentication system that locks down an account for a certain period of time after three failed login attempts. Ronaldo sees this as a trade off between usability and security, but I see it more as an added security issue in that it allows malicious third parties to lock other user’s accounts armed only with their username.
[... 398 words]Nasty new IE vulnerability
Most people reading are probably aware of the common trick whereby spammers and other assorted ne’er-do-wells publish URLs with usernames that look like hostnames to fool people in to trusting a malicious site—for example, http://www.microsoft.com&session%123123123@simon.incutio.com. This trick is frequently used by spammers to steal people’s PayPal accounts, by tricking them in to “resetting” their password at a site owned by the spammer but disguised as PayPal.com.
[... 164 words]High security is low security
Via Crypto-Gram, a great piece from Bruce Tognazzini about how tough security measures can actively reduce the security of a system:
[... 225 words]Signing comments on blogs
Adrian Holovaty has implemented reserved comment names in his blog, a feature that prevents anyone apart from him from using the names “Adrian”, “Adrian H.” or “Adrian Holovaty” when posting a comment. François Nonnenmacher suggests extending the idea to allow people to “confirm” their authorship of comments on any blog using a TrackBack sent to their site that in turn causes them to be sent an alert email, which they can then use to confirm their comment. I like his idea of authentication based on URLs (email addresses are no good; they should not be publically displayed for fear of spam harvesters) but I think I’ve come up with an alternative authentication scheme that removes the need for the user to manually confirm authorship. This is pretty complicated, so bare with me.
[... 762 words]Hashing client-side data
Via Scott, a clever PHP technique for ensuring data sent to the browser as a cookie or hidden form variable isn’t tampered with by the user:
[... 248 words]Remembering passwords
Via Scott, an article with some great tips on remembering your passwords. It includes the following vitally important tip:
[... 273 words]