Feeds

Facebook takes the Captcha rap

Stop the word verification madness

Reducing security risks from open source software

From time to time we capture word verification silliness for posterity. It's been a while, but we've got another for you, this time from Facebook - and this time it ain't so silly.

The text reads: "rape now". It was displayed next to the picture of a female work colleague our tipster (a Reg reader, of course) was adding to his list of Facebook friends?

Screenshot from Facebook captcha that reads: "rape now"

While Facebook calls such scripts "security checks," the rest of the world knows them as captchas, short for completely automated public Turing Test to tell computers and humans apart. The point is to display an image that's not easily recognizable to a computer to ensure a real person is on the other end of a transaction.

The offending captcha was generated by ReCaptcha, a project sponsored by Carnegie Mellon University researchers working on a novel way of digitizing old books. Optical character recognition can stumble on as much as 30 per cent of the words it encounters. ReCaptcha displays them to users of Facebook and other sites. When they type in the corresponding text, the mystery is solved.

"Although there is very heavy filtering against offensive CAPTCHAs (we have over 1000 words in our list of offensive terms), in very rare cases, inappropriate words can be shown," Luis von Ahn, a professor working on the project explained in an email. "We work very hard to keep such words out of the system, but in general it is impossible to guarantee that nothing offensive will ever be displayed."

He said ReCaptcha displays about 30 million images every day and generally gets fewer than one complaint each month.

We knew there was something strange about the words being displayed on Facebook's security check. While cycling through we got combinations that included "mutton synagogue," Toledo playmates" and "wiped president."

Von Ahn says this isn't the first cockup to affect a captcha, and pointed us to several examples, two of which we include below.

Screenshot of Google Adwords captcha that reads: "pness"

Screenshot of Google captcha that reads: "nodick"

We see his point. ®

Mobile application security vulnerability report

More from The Register

next story
LibreSSL RNG bug fix: What's all the forking fuss about, ask devs
Blow to bit-spitter 'tis but a flesh wound, claim team
Microsoft: You NEED bad passwords and should re-use them a lot
Dirty QWERTY a perfect P@ssword1 for garbage websites
Manic malware Mayhem spreads through Linux, FreeBSD web servers
And how Google could cripple infection rate in a second
NUDE SNAPS AGENCY: NSA bods love 'showing off your saucy selfies'
Swapping other people's sexts is a fringe benefit, says Snowden
Own a Cisco modem or wireless gateway? It might be owned by someone else, too
Remote code exec in HTTP server hands kit to bad guys
British data cops: We need greater powers and more money
You want data butt kicking, we need bigger boots - ICO
Crooks fling banking Trojan at Japanese smut site fans
Wait - they're doing online banking with an unpatched Windows PC?
NIST told to grow a pair and kick NSA to the curb
Lrn2crypto, oversight panel tells US govt's algorithm bods
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
The Essential Guide to IT Transformation
ServiceNow discusses three IT transformations that can help CIO's automate IT services to transform IT and the enterprise.
Mobile application security vulnerability report
The alarming realities regarding the sheer number of applications vulnerable to attack, and the most common and easily addressable vulnerability errors.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Consolidation: the foundation for IT and business transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.