Posts Tagged: 2FA


1
Aug 18

Reddit Breach Highlights Limits of SMS-Based Authentication

Reddit.com today disclosed that a data breach exposed some internal data, as well as email addresses and passwords for some Reddit users. As Web site breaches go, this one doesn’t seem too severe. What’s interesting about the incident is that it showcases once again why relying on mobile text messages (SMS) for two-factor authentication (2FA) can lull companies and end users into a false sense of security.

In a post to Reddit, the social news aggregation platform said it learned on June 19 that between June 14 and 18 an attacker compromised a several employee accounts at its cloud and source code hosting providers.

Reddit said the exposed data included internal source code as well as email addresses and obfuscated passwords for all Reddit users who registered accounts on the site prior to May 2007. The incident also exposed the email addresses of some users who had signed up to receive daily email digests of specific discussion threads.

Of particular note is that although the Reddit employee accounts tied to the breach were protected by SMS-based two-factor authentication, the intruder(s) managed to intercept that second factor.

“Already having our primary access points for code and infrastructure behind strong authentication requiring two factor authentication (2FA), we learned that SMS-based authentication is not nearly as secure as we would hope, and the main attack was via SMS intercept,” Reddit disclosed. “We point this out to encourage everyone here to move to token-based 2FA.”

Reddit didn’t specify how the SMS code was stolen, although it did say the intruders did not hack Reddit employees’ phones directly. Nevertheless, there are a variety of well established ways that attackers can intercept one-time codes sent via text message.

In one common scenario, known as a SIM-swap, the attacker masquerading as the target tricks the target’s mobile provider into tying the customer’s service to a new SIM card that the bad guys control. A SIM card is the tiny, removable chip in a mobile device that allows it to connect to the provider’s network. Customers can request a SIM swap when their existing SIM card has been damaged, or when they are switching to a different phone that requires a SIM card of another size.

Another typical scheme involves mobile number port-out scams, wherein the attacker impersonates a customer and requests that the customer’s mobile number be transferred to another mobile network provider. In both port-out and SIM swap schemes, the victim’s phone service gets shut off and any one-time codes delivered by SMS (or automated phone call) get sent to a device that the attackers control. Continue reading →


23
Jul 18

Google: Security Keys Neutralized Employee Phishing

Google has not had any of its 85,000+ employees successfully phished on their work-related accounts since early 2017, when it began requiring all employees to use physical Security Keys in place of passwords and one-time codes, the company told KrebsOnSecurity.

A YubiKey Security Key made by Yubico. The basic model featured here retails for $20.

Security Keys are inexpensive USB-based devices that offer an alternative approach to two-factor authentication (2FA), which requires the user to log in to a Web site using something they know (the password) and something they have (e.g., a mobile device).

A Google spokesperson said Security Keys now form the basis of all account access at Google.

“We have had no reported or confirmed account takeovers since implementing security keys at Google,” the spokesperson said. “Users might be asked to authenticate using their security key for many different apps/reasons. It all depends on the sensitivity of the app and the risk of the user at that point in time.”

The basic idea behind two-factor authentication is that even if thieves manage to phish or steal your password, they still cannot log in to your account unless they also hack or possess that second factor.

The most common forms of 2FA require the user to supplement a password with a one-time code sent to their mobile device via text message or an app. Indeed, prior to 2017 Google employees also relied on one-time codes generated by a mobile app — Google Authenticator.

In contrast, a Security Key implements a form of multi-factor authentication known as Universal 2nd Factor (U2F), which allows the user to complete the login process simply by inserting the USB device and pressing a button on the device. The key works without the need for any special software drivers.

Once a device is enrolled for a specific Web site that supports Security Keys, the user no longer needs to enter their password at that site (unless they try to access the same account from a different device, in which case it will ask the user to insert their key).

U2F is an emerging open source authentication standard, and as such only a handful of high-profile sites currently support it, including Dropbox, Facebook, Github (and of course Google’s various services). Most major password managers also now support U2F, including Dashlane, and Keepass. Duo Security [full disclosure: an advertiser on this site] also can be set up to work with U2F.

With any luck, more sites soon will begin incorporating the Web Authentication API — also known as “WebAuthn” — a standard put forth by the World Wide Web Consortium in collaboration with the FIDO Alliance. The beauty of WebAuthn is that it eliminates the need for users to constantly type in their passwords, which negates the threat from common password-stealing methods like phishing and man-in-the-middle attacks.

Currently, U2F is supported by Chrome, Mozilla Firefox, and Opera. In both Firefox and Quantum (the newer, faster version of Firefox), U2F is not enabled by default. To turn it on, type “about:config” in the browser bar, type or paste “security.webauth.u2f” and double-click the resulting entry to change the preference’s value from “false” to “true.”

Microsoft says it expects to roll out updates to its flagship Edge browser to support U2F later this year. According to a recent article at 9to5Mac.com, Apple has not yet said when or if it will support the standard in its Safari browser. Continue reading →


24
Mar 17

Phishing 101 at the School of Hard Knocks

A recent, massive spike in sophisticated and successful phishing attacks is prompting many universities to speed up timetables for deploying mandatory two-factor authentication (2FA) — requiring a one-time code in addition to a password — for access to student and faculty services online. This is the story of one university that accelerated plans to require 2FA after witnessing nearly twice as many phishing victims in the first two-and-half months of this year than it saw in all of 2015.

bgBowling Green State University in Ohio has more than 20,000 students and faculty, and like virtually any other mid-sized state school its Internet users are constantly under attack from scammers trying to phish login credentials for email and online services.

BGSU had planned later this summer to make 2FA mandatory for access to the school’s portal — the primary place where students register for classes, pay bills, and otherwise manage their financial relationship to the university.

That is, until a surge in successful phishing attacks resulted in several students having bank accounts and W-2 tax forms siphoned.

On March 1, 2017 all BGSU account holders were required to change their passwords, and on March 15, 2017 two-factor authentication (Duo) protection was placed in front of the MyBGSU portal [full disclosure: Duo is a longtime advertiser on KrebsOnSecurity].

Matt Haschak, director of IT security and infrastructure at BGSU, said the number of compromised accounts detected at BGSU has risen from 250 in calendar year 2015 to 1000 in 2016, and to approximately 400 in the first 75 days of 2017.

Left unchecked, phishers are on track to steal credentials from nearly 10 percent of the BGSU student body by the end of this year. The university has offered 2FA options for its portal access since June 2016, but until this month few students or faculty were using it, Haschak said.

“We saw very low adoption when it was voluntary,” he said. “And typically the people who adopted it were not my big security risks.”

Haschak said it’s clear that the scale and size of the phishing problem is hardly unique to BGSU.

“As I keep preaching to our campus community, this is not unique to BGSU,” Haschak said. “I’ve been talking a lot lately to my counterparts at universities in Ohio and elsewhere, and we’re all getting hit with these attacks very heavily right now. Some of the phishing scams are pretty good, but unfortunately some are god-awful, and I think people are just not thinking or they’re too busy in their day, they receive something on their phone and they just click it.”

Last month, an especially tricky phishing scam fooled several students who are also employed at the university into giving away their BGSU portal passwords, after which the thieves changed the victims’ direct deposit information so that their money went to accounts controlled by the phishers.

In other scams, the phishers would change the routing number for a bank account tied to a portal user, and then cancel that student’s classes near the beginning of a semester — thus kicking off a fraudulent refund.

One of the victims even had a fraudulent tax refund request filed in her name with the IRS as a result, Haschak said.

“They went in and looked at her W-2 information, which is also available via the portal,” he said. Continue reading →