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Items tagged security in 2009

Filters: Year: 2009 × security × Sorted by date


Critical Mac OS X Java Vulnerabilities. There’s a five month old Java arbitrary code execution vulnerability which hasn’t yet been patched by Apple. Disable Java applets in your browser until it’s fixed, or random web pages could execute commands on your machine as your user account. # 19th May 2009, 7:07 pm

moot wins, Time Inc. loses. The Time.com poll hack was more sophisticated than I first thought... Time implemented reCAPTCHA half way through the voting period, but the 4chan community fought back with a custom interface that crowdsourced the job of voting and let individuals submit up to 30 votes a minute. # 29th April 2009, 11:13 am

OAuth Security Advisory 2009.1. It’s a show-stopper: an attacker can start an OAuth permission request flow from a consumer site, then trick another user from the same site in to completing that flow and hence authorising the attacker to act on their behalf. A fix to the spec is forthcoming; in the meantime, don’t start an OAuth flow from an untrusted location. # 23rd April 2009, 3:06 pm

Inside the precision hack. How 4chan members subverted a Time.com online poll to reorder the options and spell out their own message. Partly poor application design from Time (the first version used a GET request without input validation), but I challenge anyone to design an anonymous online poll that can’t be fixed using the more sophisticated techniques 4chan eventually deployed based on HTTP proxies. # 20th April 2009, 8:36 pm

Reducing XSS by way of Automatic Context-Aware Escaping in Template Systems (via) The Google Online Security Blog reminds us that simply HTML-escaping everything isn’t enough—the type of escaping needed depends on the current markup context, for example variables inside JavaScript blocks should be escaped differently. Google’s open source Ctemplate library uses an HTML parser to keep track of the current context and apply the correct escaping function automatically. # 14th April 2009, 9:26 am

Amazon Says Listing Problem Was an Error, Not a Hack (via) “A friend within the company told him that someone working on Amazon’s French site mistagged a number of keyword categories, including the ’Gay and Lesbian’ category, as pornographic, using what’s known internally as the Browse Nodes tool. Soon the mistake affected Amazon sites worldwide.” # 14th April 2009, 8:32 am

How to cause moral outrage from the entire Internet in ten lines of code. Looks legit—the author claims to have sparked this weekend’s #amazonfail moral outrage (where Amazon where accused of removing Gay and Lesbian books from their best seller rankings) by exploiting a CSRF hole in Amazon’s “report as inappropriate” feature to trigger automatic takedowns. EDIT: His claim is disputed elsewhere (see comments) # 13th April 2009, 7:48 pm

17-year-old claims responsibility for Twitter worm. It was a text book XSS attack—the URL on the user profile wasn’t properly escaped, allowing an attacker to insert a script element linking out to externally hosted JavaScript which then used Ajax to steal any logged-in user’s anti-CSRF token and use it to self-replicate in to their profile. # 12th April 2009, 7:22 pm

Pwn2Own trifecta: Hacker exploits IE8, Firefox, Safari. You just can’t trust browser security: Current versions of Safari, IE8 and Firefox all fell to zero-day flaws at an exploit competition. None of the vulnerabilities have been disclosed yet. # 19th March 2009, 3:30 pm

Understanding Bidirectional (BIDI) Text in Unicode. It turns out you need to sanitise user input to ensure there are no unicode characters that switch your site’s regular text to RTL. # 15th March 2009, 4:37 am

Twitter Don’t Click Exploit. Someone ran a successful ClickJacking exploit against Twitter users, using a transparent iframe holding the Twitter homepage with a status message fed in by a query string parameter. Thiss will definitely help raise awareness of ClickJacking! Twitter has now added framebusting JavaScript to prevent the exploit. # 12th February 2009, 7:56 pm

Ehy IE8, I Can Has Some Clickjacking Protection? (via) IE8 has built-in protection against clickjacking, but it’s opt-in (with a custom HTTP header) and IE only. It turns out the usual defence against clickjacking (using framebusting JavaScript) doesn’t work in IE as it can be worked around with a security=“restricted” attribute on an iframe. # 29th January 2009, 1:39 pm

OWASP: XSS Prevention Cheat Sheet. Comprehensive set of rules for avoiding XSS—there’s a bit more to it than just escaping all output variables, since you have to take markup context in to account. # 24th January 2009, 11:58 pm

CSRF is not a security issue for the Web. A well-designed Web service should be capable of receiving requests directed by any host, by design, with appropriate authentication where needed. If browsers create a security issue because they allow scripts to automatically direct requests with stored security credentials onto third-party sites, without any user intervention/configuration, then the obvious fix is within the browser.

Roy Fielding # 23rd January 2009, 8:14 am

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]

Weak Password Brings “Happiness” to Twitter Hacker. The full story on the Twitter admin account hack. I bet there are a LOT of web applications out there that don’t track and rate-limit failed password attempts. # 7th January 2009, 12:04 pm

The Twitter administrator hack was a dictionary attack. I quoted Blaine earlier suggesting that the recent Twitter mass-hack was due to a Twitter admin password being scooped up by a rogue third party application—this was not the case, as Alex Payne explains in a comment. # 6th January 2009, 11:56 pm

As more details become available, it seems what happened is that a Twitter administrator (i.e., employee) gave their password to a 3rd party site because their API requires it, which was then used to compromise Twitter’s admin interface.

Blaine Cook # 6th January 2009, 9:37 am

The username/password key’s major disadvantage is that it open all the doors to the house. The OAuth key only opens a couple doors; the scope of the credentials is limited. That’s a benefit, to be sure, but in Twitter’s case, a malicious application that registered for OAuth with both read and write privileges can do most evil things a user might be worried about.

Alex Payne # 5th January 2009, 10:47 am

Antipatterns for sale. Twply collected over 800 Twitter usernames and passwords (OAuth can’t arrive soon enough) and was promptly auctioned off on SitePoint to the highest bidder. # 2nd January 2009, 10:48 am