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Tweet from David Risney

2016 Jun 6, 10:37
History & design of the biohazard symbol ☣: http://99percentinvisible.org/article/biohazard-symbol-designed-to-be-memorable-but-meaningless/  Creator sends angry letter over sartorial usage
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Retweet of sharonodea

2015 Sep 30, 5:53
Founder of #Peeple, an app designed to collect unsolicited feedback doesn't appear to like unsolicited feedback. pic.twitter.com/MmYZW3oHw4
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Tweet from David_Risney

2015 Sep 19, 1:08
Designing the least JPG compressible fabric pattern: http://dsp.stackexchange.com/questions/2010/what-is-the-least-jpg-compressible-pattern-camera-shooting-piece-of-cloth-sca …. This is the anti @ericlaw
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Gamers Messed With The Steam Sale, Then Valve Changed The Rules

2014 Jun 24, 3:51

Applied game theory 101: Valve’s Steam Summer Sale involves a meta game with teams of Steam users competing for daily prizes. On Reddit the players join together to take turns winning daily. Valve gets wise and performs an existential attack, changing the rules to make it harder for players to want to coordinate.

Still, that all the players joined together to game the system gives me hope for humanity. Its a self organized solution to a tragedy of the commons problem. Only in this case the tragedy is by design and is updated to be more tragic.

PermalinkCommentsgame video-game game-theory valve

Mario Maker - Design Mario levels on the Wii U. Time to break...

2014 Jun 10, 3:57


Mario Maker - Design Mario levels on the Wii U. Time to break out my Mario level design documents from when I was 8.

PermalinkCommentsgame video-game Mario Nintendo video

URI Design and Ownership - IETF Draft

2014 May 21, 2:06

URI Design & Ownership - On the issues with and alternatives to requiring well known filenames and extensions in URIs. You must love the draft’s URI.

PermalinkCommentstechnical uri

Where the best designers go to find photos and graphics

2014 Jan 5, 3:09

List of useful free or CC licensed photography and icon sites.

PermalinkCommentsfree cc photo photography icon

Promises/A+

2013 Dec 17, 9:03

What is good and common of all JS promise designs collected as Promises/A+

Promises/A+

An open standard for sound, interoperable JavaScript promises—by implementers, for implementers.

PermalinkCommentstechnical javascript

laughingsquid: Windows 95 Tips, Tricks, and Tweaks Some very...

2012 Nov 14, 5:39


laughingsquid:

Windows 95 Tips, Tricks, and Tweaks

Some very H. P. Lovecraft style redesigns of some classic Win95 UI.

PermalinkCommentshorror humor windows windows-95

Stripe CTF - Level 5

2012 Sep 11, 5:00

Level 5 of the Stripe CTF revolved around a design issue in an OpenID like protocol.

Code

    def authenticated?(body)
body =~ /[^\w]AUTHENTICATED[^\w]*$/
end

...

if authenticated?(body)
session[:auth_user] = username
session[:auth_host] = host
return "Remote server responded with: #{body}." \
" Authenticated as #{username}@#{host}!"

Issue

This level is an implementation of a federated identity protocol. You give it an endpoint URI and a username and password, it posts the username and password to the endpoint URI, and if the response is 'AUTHENTICATED' then access is allowed. It is easy to be authenticated on a server you control, but this level requires you to authenticate from the server running the level. This level only talks to stripe CTF servers so the first step is to upload a document to the level 2 server containing the text 'AUTHENTICATED' and we can now authenticate on a level 2 server. Notice that the level 5 server will dump out the content of the endpoint URI and that the regexp it uses to detect the text 'AUTHENTICATED' can match on that dump. Accordingly I uploaded an authenticated file to

https://level02-2.stripe-ctf.com/user-ajvivlehdt/uploads/authenticated
Using that as my endpoint URI means authenticating as level 2. I can then choose the following endpoint URI to authenticate as level 5.
https://level05-1.stripe-ctf.com/user-qtoyekwrod/?pingback=https%3A%2F%2Flevel02-2.stripe-ctf.com%2Fuser-ajvivlehdt%2Fuploads%2Fauthenticated&username=a&password=a
Navigating to that URI results in the level 5 server telling me I'm authenticated as level 2 and lists the text of the level 2 file 'AUTHENTICATED'. Feeding this back into the level 5 server as my endpoint URI means level 5 seeing 'AUTHENTICATED' coming back from a level 5 URI.

Notes

I didn't see any particular code review red flags, really the issue here is that the regular expression testing for 'AUTHENTICATED' is too permisive and the protocol itself doesn't do enough. The protocol requires only a set piece of common literal text to be returned which makes it easy for a server to accidentally fall into authenticating. Having the endpoint URI have to return variable text based on the input would make it much harder for a server to accidentally authenticate.

PermalinkCommentsinternet openid security stripe-ctf technical web

Stripe CTF - XSS, CSRF (Levels 4 & 6)

2012 Sep 10, 4:43

Level 4 and level 6 of the Stripe CTF had solutions around XSS.

Level 4

Code

> Registered Users 

  • <% @registered_users.each do |user| %>
    <% last_active = user[:last_active].strftime('%H:%M:%S UTC') %>
    <% if @trusts_me.include?(user[:username]) %>

  • <%= user[:username] %>
    (password: <%= user[:password] %>, last active <%= last_active %>)
  • Issue

    The level 4 web application lets you transfer karma to another user and in doing so you are also forced to expose your password to that user. The main user page displays a list of users who have transfered karma to you along with their password. The password is not HTML encoded so we can inject HTML into that user's browser. For instance, we could create an account with the following HTML as the password which will result in XSS with that HTML:

    
    
    This HTML runs script that uses jQuery to post to the transfer URI resulting in a transfer of karma from the attacked user to the attacker user, and also the attacked user's password.

    Notes

    Code review red flags in this case included lack of encoding when using user controlled content to create HTML content, storing passwords in plain text in the database, and displaying passwords generally. By design the web app shows users passwords which is a very bad idea.

    Level 6

    Code



    ...

    def self.safe_insert(table, key_values)
    key_values.each do |key, value|
    # Just in case people try to exfiltrate
    # level07-password-holder's password
    if value.kind_of?(String) &&
    (value.include?('"') || value.include?("'"))
    raise "Value has unsafe characters"
    end
    end

    conn[table].insert(key_values)
    end

    Issue

    This web app does a much better job than the level 4 app with HTML injection. They use encoding whenever creating HTML using user controlled data, however they don't use encoding when injecting JSON data into script (see post_data initialization above). This JSON data is the last five most recent messages sent on the app so we get to inject script directly. However, the system also ensures that no strings we write contains single or double quotes so we can't get out of the string in the JSON data directly. As it turns out, HTML lets you jump out of a script block using no matter where you are in script. For instance, in the middle of a value in some JSON data we can jump out of script. But we still want to run script, so we can jump right back in. So the frame so far for the message we're going to post is the following:

    
    
PermalinkCommentscsrf encoding html internet javascript percent-encoding script security stripe-ctf technical web xss

Stripe Web Security CTF Summary

2012 Aug 30, 5:00

I was the 546th person to complete Stripe's web security CTF and again had a ton of fun applying my theoretical knowledge of web security issues to the (semi-)real world. As I went through the levels I thought about what red flags jumped out at me (or should have) that I could apply to future code reviews:

Level Issue Code Review Red Flags
0 Simple SQL injection No encoding when constructing SQL command strings. Constructing SQL command strings instead of SQL API
1 extract($_GET); No input validation.
2 Arbitrary PHP execution No input validation. Allow file uploads. File permissions modification.
3 Advanced SQL injection Constructing SQL command strings instead of SQL API.
4 HTML injection, XSS and CSRF No encoding when constructing HTML. No CSRF counter measures. Passwords stored in plain text. Password displayed on site.
5 Pingback server doesn't need to opt-in n/a - By design protocol issue.
6 Script injection and XSS No encoding while constructing script. Deny list (of dangerous characters). Passwords stored in plain text. Password displayed on site.
7 Length extension attack Custom crypto code. Constructing SQL command string instead of SQL API.
8 Side channel attack Password handling code. Timing attack mitigation too clever.

More about each level in the future.

PermalinkCommentscode-review coding csrf html internet programming script security sql stripe technical web xss

Web Security Contest - Stripe CTF

2012 Aug 27, 4:18

Stripe is running a web security capture the flag - a series of increasingly difficult web security exploit challenges. I've finished it and had a lot of fun. Working on a web browser I knew the theory of these various web based attacks, but this was my first chance to put theory into practice with:

  • No adverse consequences
  • Knowledge that there is a fun security exploit to find
  • Access to the server side source code

Here's a blog post on the CTF behind the scenes setup which has many impressive features including phantom users that can be XSS/CSRF'ed.

I'll have another post on my difficulties and answers for the CTF levels after the contest is over on Wed, but if you're looking for hints, try out the CTF chatroom or the level specific CTF chatroom.

PermalinkCommentscontest security technical

Zineth Release Trailer (by Russell Honor) This is a student...

2012 Aug 10, 2:24


Zineth Release Trailer (by Russell Honor)

This is a student game. Amazing design and music. A more abstract, massive and fast Jet Set Radio.

PermalinkCommentsgame video-game jet-set-radio free

Newsroom: Miscellaneous: New Online Tool Gives Public Wider Access to Key U.S. Statistics

2012 Jul 28, 2:35

The U.S. Census Bureau today released a new online service that makes key demographic, socio-economic and housing statistics more accessible than ever before. The Census Bureau’s first-ever public Application Programming Interface (API) allows developers to design Web and mobile apps to explore or learn more about America’s changing population and economy.

PermalinkCommentstechnical api census statistics stats web restful rest

Wooden Train Set Dining Table (by 3foot3design)

2012 Jul 18, 3:28


Wooden Train Set Dining Table (by 3foot3design)

PermalinkCommentstrain brio furniture video

“Fuck You, Pay Me” is a talk on contracts, payments,...

2012 Jun 25, 2:06


Fuck You, Pay Me” is a talk on contracts, payments, etc. for free-lance designers.

PermalinkCommentsbusiness web-desgin video technical

Crypto breakthrough shows Flame was designed by world-class scientists | Ars Technica

2012 Jun 7, 9:12

So this is another Stuxnet by Israel/US?

The analysis reinforces theories that researchers from Kaspersky Lab, CrySyS Lab, and Symantec published almost two weeks ago. Namely, Flame could only have been developed with the backing of a wealthy nation-state. … “It’s not a garden-variety collision attack, or just an implementation of previous MD5 collisions papers—which would be difficult enough,” Matthew Green, a professor specializing in cryptography in the computer science department at Johns Hopkins University, told Ars. “There were mathematicians doing new science to make Flame work.”

PermalinkCommentstechnical security web internet md5 cryptography flame

wired: [via motherjones]: theweekmagazine: Sticking to an...

2012 Jun 7, 3:29


wired:

[via motherjones]:

theweekmagazine:

Sticking to an exercise routine takes dedication, and many fitness junkies swear that a running companion can be a huge help. That’s why researchers have developed “Joggobot,” a quad-rotor helicopter drone designed to motivate joggers by flying in front of them. 

The aerial robot uses its camera to spot a colorful pattern on a T-shirt worn by the jogger, and flies at a safe distance ahead. The runner can control Joggobot using a smartphone: In “companion mode,” the drone simply maintains the jogger’s pace; in “coach mode,” it pushes its human trainee a little faster.

Don’t worry, there’s a video

Science!

Maybe it should chase you instead?

PermalinkCommentshumor exercise robot future video

EFF White Paper Outlines How Businesses Can Avoid Assisting Repressive Regimes

2012 Apr 18, 6:24

A House subcommittee has passed the Global Online Freedom Act (GOFA), which would require disclosure from companies about their human rights practices and limit the export of technologies that “serve the primary purpose of” facilitating government surveillance or censorship to countries designated as “Internet-restricting.”

PermalinkCommentstechnical human-rights eff software government law surveillance
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