eHarmony data breach lessons: Cracking hashed passwords can be too easy

[security curmudgeon <jericho () attrition org>]

---------- Forwarded message ----------
From: InfoSec News <alerts () infosecnews org>

https://www.networkworld.com/news/2012/070612-eharmony-data-breach-260709.html

By Ellen Messmer
Network World
July 06, 2012

Last month the dating site eHarmony suffered a data breach in which more 
than 1.5 million eHarmony password hashes were stolen and later dumped 
online by the hacker gang called Doomsday Preppers. The crypto-based 
"hashing" process is supposed to conceal stored passwords, but Trustwave's 
SpiderLabs division says eHarmony could have done this process a lot 
better because it only took 72 hours to crack about 80% of 1.5 million 
eHarmony hashed passwords that were dumped.

Cracking the dumped eHarmony passwords wasn't too hard, says Mike Kelly, 
security analyst at SpiderLabs, which used tools such as oclHashcat and 
John the Ripper. In fact, he says it was one of the "easiest" challenges 
he ever faced. There are many reasons why this is so, starting with the 
fact the cracked passwords may have been "hashed," but they weren't 
"salted," which he says "would drastically increase the time it would take 
to crack them."

He points out that hashing the passwords with a crypto algorithm is a good 
start to scramble the password, but by adding the "salt" of a random 
string in the process, the "salted hash" is far stronger protection. 
eHarmony was also using the MD5 format, which is considered somewhat weak 
by cryptographers today, Kelly adds.

Other aspects that made the eHarmony password crack so easy is that "they 
were storing the passwords in case-insensitive mode," says Kelly. "They 
eliminated the upper-case letters," adding that this drastically reduced 
the time to crack them. SpiderLabs acknowledges the possibility that the 
attackers who hit eHarmony may have changed some passwords since no single 
password was found more than three times. The most popular length of 
password was seven characters, SpiderLabs said.

[...]
_______________________________________________
Dataloss Mailing List (dataloss () datalossdb org)
Archived at http://seclists.org/dataloss/
Unsubscribe at http://datalossdb.org/mailing_list

Supporters:

Risk Based Security (http://www.riskbasedsecurity.com/)
Risk Based Security equips organizations with security intelligence, risk
management services and on-demand security solutions to establish
customized risk-based programs to address information security and
compliance challenges. 

Tenable Network Security (http://www.tenable.com/)
Tenable Network Security provides a suite of solutions which unify real-time
vulnerability, event and compliance monitoring into a single, role-based, interface
for administrators, auditors and risk managers to evaluate, communicate and
report needed information for effective decision making and systems management.