Feeds

Facebook login page still leaks sensitive info

Security malpractice 101

Providing a secure and efficient Helpdesk

Facebook's login system continues to spill information that can be helpful to phishers, social engineers and other miscreants attempting to scam the more than 500 million active users of the social networking site.

When a legitimate email address is entered along with an incorrect password, the authentication system returns an error that reads: “Please re-enter your password. The password you entered is incorrect. Please try again (make sure your caps lock is off).” When an email address that doesn't belong to a Facebook user is entered, the response is: “Incorrect Email. The email you entered does not belong to any account.”

The difference in the wording makes it possible for anyone to discern whether a given email address is registered on Facebook, even when the corresponding password is unknown. It was flagged to us by Reg reader Ben Prescott, a security analyst for EMC Corporation's Critical Incident Response Center, who calls it “one of the oldest security malpractices in the book.”

The configuration makes it possible to verify the validity of huge numbers of email addresses. It has been in place since last week, when Facebook developers fixed a much more serious bug that allowed attackers to match unknown email addresses with users' pictures and full names. It worked even for accounts that were configured to be private. It came to light after a researcher published a simple script that could quickly scrape large numbers of names and pictures that corresponded to email addresses.

While the new setup offers considerably less information, it could still be helpful for people trying to guess the email addresses of people in a given company or organization. And there's no reason this hack couldn't be automated, either.

It wouldn't be surprising if Facebook changed this setting soon. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
SMASH the Bash bug! Apple and Red Hat scramble for patch batches
'Applying multiple security updates is extremely difficult'
Shellshock: 'Larger scale attack' on its way, warn securo-bods
Not just web servers under threat - though TENS of THOUSANDS have been hit
Apple's new iPhone 6 vulnerable to last year's TouchID fingerprint hack
But unsophisticated thieves need not attempt this trick
Hackers thrash Bash Shellshock bug: World races to cover hole
Update your gear now to avoid early attacks hitting the web
Oracle SHELLSHOCKER - data titan lists unpatchables
Database kingpin lists 32 products that can't be patched (yet) as GNU fixes second vuln
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Researchers tell black hats: 'YOU'RE SOOO PREDICTABLE'
Want to register that domain? We're way ahead of you.
Stunned by Shellshock Bash bug? Patch all you can – or be punished
UK data watchdog rolls up its sleeves, polishes truncheon
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.